The fraction equivalent to the repeating decimal 0.35¯¯¯¯¯ is 35/99.
To determine the fraction equivalent to the repeating decimal 0.35¯¯¯¯¯, these steps:
Step 1: Let's assign a variable to the repeating decimal. Let x = 0.35¯¯¯¯¯.
Step 2: Multiply both sides of the equation by 100 to remove the repeating decimal:
100x = 35.353535...
Step 3: Subtract the original equation from the one obtained in Step 2 to eliminate the repeating part:
100x - x = 35.353535... - 0.35¯¯¯¯¯
99x = 35
Step 4: Solve for x by dividing both sides of the equation by 99:
x = 35/99.
To know more about fraction here
https://brainly.com/question/10354322
#SPJ4
Find the area of each regular polygon. Leave answer in simplest form.
The areas of the regular polygons are listed below:
Case 8: A = 166.277
Case 10: A = 166.277
Case 12: A = 779.423
Case 14: A = 905.285
Case 16: A = 678.964
Case 18: A = 332.554
Case 20: A = 1122.369
Case 22: A = 166.277
How to determine the area of a regular polygon
In this problem we must determine the areas of eight regular polygons, whose formula is now shown below:
A = 0.5 · (n · l · a)
a = 0.5 · l / tan (180 / n)
Where:
a - Apothemal - Side lengthn - Number sidesNow we proceed to determine the area of each polygon:
Case 8:
l = 2 · a · tan (180 / n)
l = 2 · 4√3 · tan 30°
l = 8√3 · (√3 / 3)
l = 8
A = 0.5 · (n · l · a)
A = 0.5 · 6 · 8 · 4√3
A = 166.277
Case 10:
a = 0.5 · l / tan (180 / n)
a = 0.5 · 8 / tan 30°
a = 4 / (√3 / 3)
a = 4√3
A = 0.5 · (n · l · a)
A = 0.5 · 6 · 8 · 4√3
A = 166.277
Case 12:
a = 0.5 · l / tan (180 / n)
a = 0.5 · 10√3 / tan 30°
a = 5√3 / (√3 / 3)
a = 15
A = 0.5 · (n · l · a)
A = 0.5 · 6 · 10√3 · 15
A = 779.423
Case 14:
l = 2 · a · tan (180 / n)
l = 2 · (28√3 / 3) · tan 30°
l = (56√3 / 3) · (√3 / 3)
l = (56 · 3 / 9)
l = 56 / 3
A = 0.5 · (n · l · a)
A = 0.5 · [6 · (56 / 3) · (28√3 / 3)]
A = 905.285
Case 16:
l = 2 · a · tan (180 / n)
l = 2 · 14 · tan 30°
l = 28 · √3 / 3
l = 28√3 / 3
A = 0.5 · (n · l · a)
A = 0.5 · 6 · (28√3 / 3) · 14
A = 678.964
Case 18:
l = 2 · a · tan (180 / n)
l = 2 · 8 · tan 60°
l = 16√3
A = 0.5 · (n · l · a)
A = 0.5 · 3 · 16√3 · 8
A = 332.554
Case 20:
a = 0.5 · l / tan (180 / n)
a = 0.5 · 12√3 / tan 30°
a = 6√3 / (√3 / 3)
a = 18
A = 0.5 · (n · l · a)
A = 0.5 · 6 · 12√3 · 18
A = 1122.369
Case 22:
a = 0.5 · l / tan (180 / n)
a = 0.5 · 8 / tan 30°
a = 4 / (√3 / 3)
a = 4√3
A = 0.5 · (n · l · a)
A = 0.5 · 6 · 8 · 4√3
A = 166.277
To learn more on areas of regular polygons: https://brainly.com/question/32319474
#SPJ1
Amy, Zac, and Harry are running a race.
Zac has run
1/2of the race.
Amy has run
3/4of the race.
Harry has run
1/4of the race.
Who has run the shortest distance?
Explain your answer.
Answer: Harry
Step-by-step explanation:
Because 1/4 is less than 1/2 and 3/4
Solve the system. - 3w 3y + Z= -1 -W+ 3x + y-3z= - 4 4w - x + 3z= 9 X- 3y - Z= - 10
To solve the given system of equations we can use the method of Gaussian elimination or matrix operations to find the solution. Here, I'll use the Gaussian elimination method.
First, we'll rewrite the system in matrix form:
[A | B] =
⎡ -3 3 1 | -1 ⎤
⎢ -1 3 1 | -4 ⎥
⎢ 4 -1 3 | 9 ⎥
⎣ 1 -3 -1 | -10⎦
Performing row operations to simplify the matrix:
R2 = R2 + R1
R3 = R3 - 4R1
R4 = R4 - R1
[A | B] =
⎡ -3 3 1 | -1 ⎤
⎢ 0 6 2 | -5 ⎥
⎢ 0 -13 -1 | 13 ⎥
⎣ 0 -6 -2 | -9 ⎦
Next, perform additional row operations:
R3 = R3 + (13/6)R2
R4 = R4 + (6/13)R3
[A | B] =
⎡ -3 3 1 | -1 ⎤
⎢ 0 6 2 | -5 ⎥
⎢ 0 0 0 | 0 ⎥
⎣ 0 0 0 | 0 ⎦
From the row-echelon form of the augmented matrix, we can see that the system has dependent equations. This means there are infinite solutions.
To express the solution, we can assign a parameter to one of the variables. Let's assign w = t, where t is a real number.
The solution can be written as:
w = t
x = (2/3)t - (5/6)
y = -t + (5/6)
z = s
Here, t and s can take any real values, and the solution represents an infinite number of points in 4-dimensional space.
By performing Gaussian elimination on the augmented matrix, we simplify it to row-echelon form. From the form, we observe that the system has dependent equations, indicating infinite solutions. To express the solution, we assign a parameter to one variable and express the other variables in terms of that parameter. In this case, we assign w = t and express x, y, and z accordingly. The solution represents an infinite set of points in 4-dimensional space, parameterized by t and s.
Learn more about equation here : brainly.com/question/14686792
#SPJ11
Find the area of the shaded sector of the circle.
Sorry for bad handwriting
if i was helpful Brainliests my answer ^_^
Use the method of cylindrical shells to find the volume generated by rotating the region bounded by the given curves about the y-axis.
y=3x^2 , y=18x-6x^2
The volume is 4π (absolute value) units cubed. To find the volume generated by rotating the region bounded by the curves y = 3x^2 and y = 18x - 6x^2 about the y-axis, we can use the method of cylindrical shells.
The first step is to determine the limits of integration. We need to find the x-values at which the curves intersect. Set the equations for the curves equal to each other:
3x^2 = 18x - 6x^2
Rearrange the equation and set it equal to zero:
9x^2 - 18x = 0
Factor out 9x:
9x(x - 2) = 0
This gives us two possible solutions: x = 0 and x = 2. These are the limits of integration.
Now, we need to determine the height and radius of each cylindrical shell. The height of each shell is the difference between the y-values of the curves at a particular x-value. The radius of each shell is the x-value itself.
Let's denote the height as h and the radius as r. The volume of each cylindrical shell is given by:
dV = 2πrh dx
Integrating this expression from x = 0 to x = 2 will give us the total volume:
V = ∫[0,2] 2πrh dx
To calculate the height (h), we subtract the equation of the lower curve from the equation of the upper curve:
h = (18x - 6x^2) - (3x^2) = 18x - 9x^2
The radius (r) is simply the x-value:
r = x
Now, we can substitute these values into the integral expression:
V = ∫[0,2] 2π(18x - 9x^2)(x) dx
Simplifying:
V = 2π ∫[0,2] (18x^2 - 9x^3) dx
To find the antiderivative, integrate each term separately:
V = 2π [6x^3/3 - 9x^4/4] |[0,2]
V = 2π [(2^3/3)(6) - (2^4/4)(9) - (0)]
V = 2π [16 - 18]
V = 2π [-2]
V = -4π
The volume generated by rotating the region about the y-axis is -4π (negative value indicates that the region is oriented below the y-axis).
Therefore, the volume is 4π (absolute value) units cubed.
Learn more about volume here:
https://brainly.com/question/13338592
#SPJ11
25998 x .08 x 6 whats the total interest
The calculated value of the total interest is 12479.04
How to calculate the total interestFrom the question, we have the following parameters that can be used in our computation:
25998 x .08 x 6
In the above equation, we have
Principal = 25998
Rate of interest = 0.08
Time = 6
using the above as a guide, we have the following:
Total interest = 25998 x .08 x 6
Evaluate
Total interest = 12479.04
Hence, the total interest is 12479.04
Read more about simple interest at
https://brainly.com/question/20690803
#SPJ1
a survey of 1700 commuters in new york city showed that 1190 take the subway, 640 take the bus, and 180 do not take either the bus or the subway. how many commuters take both the bus and the subway?
There are 1470 commuters take both the bus and the subway.
To find the number of commuters who take both the bus and the subway, we can use the principle of inclusion-exclusion.
Let's denote:
A = Number of commuters who take the subway
B = Number of commuters who take the bus
N = Total number of commuters
From the given information:
A = 1190 (number of commuters who take the subway)
B = 640 (number of commuters who take the bus)
N = 1700 (total number of commuters)
We also know that 180 commuters do not take either the bus or the subway.
To find the number of commuters who take both the bus and the subway, we can use the formula:
A ∪ B = A + B - A ∩ B
where A ∪ B represents the union of A and B, and A ∩ B represents the intersection of A and B.
Substituting the values we have:
A ∪ B = 1190 + 640 - 180
A ∪ B = 1650
Therefore, 1650 commuters take either the bus or the subway (or both). To find the number of commuters who take both the bus and the subway, we subtract the number of commuters who take neither:
Number of commuters who take both the bus and the subway = A ∪ B - Neither
Number of commuters who take both the bus and the subway = 1650 - 180
Number of commuters who take both the bus and the subway = 1470
Therefore, 1470 commuters take both the bus and the subway.
Learn more about set here:
brainly.com/question/8053622
#SPJ11
in a group of 42 students, 22 take history, 17 take biology and 8 take both history and biology. how many students take neither biology nor history?
Out of the 42 students, 22 take history, 17 take biology, and 8 take both history and biology. Therefore, there are 11 students who take neither biology nor history.
To find the number of students who take neither biology nor history, we need to subtract the number of students who take at least one of these subjects from the total number of students in the group.
Let's break down the information given:
Total number of students (n) = 42
Number of students taking history (H) = 22
Number of students taking biology (B) = 17
Number of students taking both history and biology (H ∩ B) = 8
To find the number of students who take at least one of these subjects, we can use the principle of inclusion-exclusion. The formula for the principle of inclusion-exclusion is:
n(A ∪ B) = n(A) + n(B) - n(A ∩ B)
In this case, A represents the set of students taking history, and B represents the set of students taking biology.
Using the formula, we can calculate the number of students taking at least one of these subjects:
n(H ∪ B) = n(H) + n(B) - n(H ∩ B)
= 22 + 17 - 8
= 31
Therefore, there are 31 students who take either history or biology or both.
To find the number of students who take neither biology nor history, we subtract this value from the total number of students:
Number of students taking neither biology nor history = Total number of students - Number of students taking at least one of the subjects
= 42 - 31
= 11
Hence, there are 11 students who take neither biology nor history.
In summary, out of the 42 students, 22 take history, 17 take biology, and 8 take both history and biology. Therefore, there are 11 students who take neither biology nor history.
Learn more about biology here
https://brainly.com/question/20659064
#SPJ11
A committee of three people is to be chosen from a group of 14 people. If Evie is in the group, what is the probability that she will be chosen for the committee?
The probability that Evie will be chosen for the committee is 0.21.
Given that, a committee of three people is to be chosen from a group of 14 people.
We know that, probability of an event = Number of favorable outcomes/Total number of outcomes.
Here, number of favorable outcomes = 3
Total number of outcomes = 14
Now, probability of an event = 3/14
= 0.21
Therefore, the probability that Evie will be chosen for the committee is 0.21.
To learn more about the probability visit:
https://brainly.com/question/11234923.
#SPJ1
use the power series method to solve the given initial-value problem. (format your final answer as an elementary function.) y'' − 2xy' 8y = 0, y(0) = 9, y'(0) = 0
The solution to the given initial-value problem, expressed as an elementary function, is y(x) = 9 - 72x - 72x².
To solve the initial-value problem y'' − 2xy' + 8y = 0 with initial conditions y(0) = 9 and y'(0) = 0 using the power series method, we can assume a power series solution of the form y(x) = ∑(n=0 to ∞) aₙxⁿ. Differentiating twice, we obtain y'' = ∑(n=0 to ∞) aₙn(n-1)xⁿ⁻² and y' = ∑(n=0 to ∞) aₙnxⁿ⁻¹. Substituting these expressions into the given differential equation and equating coefficients of like powers of x, we can derive a recurrence relation to determine the coefficients aₙ.
In the first paragraph, the summary of the answer is as follows:
By substituting the power series solution y(x) = ∑(n=0 to ∞) aₙxⁿ into the differential equation and equating coefficients, we obtain a recurrence relation for the coefficients aₙ. Solving this recurrence relation, we can determine the values of the coefficients aₙ and express the solution y(x) as an elementary function.
In the second paragraph, the explanation of the answer is provided:
Substituting the power series solution into the differential equation, we have:
∑(n=0 to ∞) aₙn(n-1)xⁿ⁻² - 2x ∑(n=0 to ∞) aₙnxⁿ⁻¹ + 8 ∑(n=0 to ∞) aₙxⁿ = 0.
Expanding the series and re-indexing the terms, we obtain:
a₀(0(-1)x⁻² + 8x⁰) + a₁(1(0)x⁻¹ - 2x¹ + 8x¹) + a₂(2(1)x⁰ - 2(1)x² + 8x²) + ∑(n=3 to ∞) (aₙn(n-1)xⁿ⁻² - 2aₙnxⁿ⁻¹ + 8aₙxⁿ) = 0.
Simplifying, we have:
8a₀ + a₁ + (2a₂ - 2a₀)x + ∑(n=3 to ∞) [(aₙn(n-1) - 2aₙn + 8aₙ)xⁿ] = 0.
To satisfy this equation, each coefficient of xⁿ must be zero. Therefore, we obtain a recurrence relation for the coefficients:
8a₀ + a₁ = 0,
2a₂ - 2a₀ = 0,
aₙn(n-1) - 2aₙn + 8aₙ = 0 for n ≥ 3.
Using the initial conditions y(0) = 9 and y'(0) = 0, we can determine the values of a₀ and a₁ as 9 and -72, respectively. Solving the recurrence relation, we find that a₂ = -72 and aₙ = 0 for n ≥ 3.
Therefore, the power series solution to the initial-value problem is:
y(x) = 9 - 72x - 72x².
Hence, the solution to the given initial-value problem, expressed as an elementary function, is y(x) = 9 - 72x - 72x².
Learn more about elementary function:
brainly.com/question/7846182
#SPJ11
if we can find a vertex map under which the adjacency matrices are unequal, then the graphs are not isomorphic.
To answer your question, we first need to understand the terms "vertex" and "isomorphic". In graph theory, a vertex is a point in a graph, while isomorphic refers to the property of two graphs having the same structure, but possibly different labels or names assigned to the vertices.
Now, let's consider the statement "if we can find a vertex map under which the adjacency matrices are unequal, then the graphs are not isomorphic." This statement is actually true. If we have two graphs, G and H, and we can find a vertex map between them such that the adjacency matrices are not equal, then we can conclude that G and H are not isomorphic.
This is because the adjacency matrix is a representation of the structure of a graph, where the rows and columns correspond to the vertices of the graph. If the adjacency matrices of two graphs are not equal, it means that the two graphs have different structures and therefore cannot be isomorphic.
In conclusion, if we can find a vertex map under which the adjacency matrices are unequal, then the graphs are not isomorphic. It's important to note that this statement only applies to simple graphs (graphs without loops or multiple edges), as the adjacency matrix of a graph with loops or multiple edges can be different even if the graphs have the same structure. Additionally, it's worth mentioning that the converse of this statement is not necessarily true – just because two graphs have equal adjacency matrices doesn't mean they are isomorphic.
To know more about isomorphic visit:
https://brainly.com/question/31399750
#SPJ11
If the cost of carpeting a floor is $2. 50 per square foot, how much will it cost to carpet a rectangular floor that is 10 feet by 12 feet?
It will cost $300 to carpet a rectangular floor that is 10 feet by 12 feet.
The cost of carpeting a rectangular floor, we need to determine the area of the floor and multiply it by the cost per square foot.
The area of a rectangle is found by multiplying its length by its width. In this case, the length is 10 feet and the width is 12 feet.
Area = Length × Width Area
Area = 10 feet × 12 feet Area
Area = 120 square feet
Now, we can calculate the cost of carpeting by multiplying the area by the cost per square foot
Cost = Area × Cost per square foot Cost
Cost = 120 square feet × $2.50 per square foot
Cost = $300
Therefore, it will cost $300 to carpet a rectangular floor that is 10 feet by 12 feet.
To know more about rectangular click here :
https://brainly.com/question/21308574
#SPJ4
Use the sample data and confidence level given below to comploto parts (a) through (d) A drug is used to help prevent blood clots in certain patients in clinical trials, among 4731 patients treated with the drug. 130 developed the adverse reaction of cause Construct a 90% confidence interval for the proportion of adverse reactions a) Find the best point estimate of the population proportion p. (Round to three decimal places as needed) b) dently the value of the margin of error (Round to three decimal places as needed c) Construct the confidence interval (Roond to the decimal pos as needed) d) We a statement that correctly interprets the confidence interval. Choose the correct answer below O A There is a chance that the true value of the population proportion will all between the lower bound and the upper bound OB 90% of sample proportions will between the lower bound and the upper bound OC One has 90% confidence that the interval from the lower bound to the upper bound actually does contain the true value of the population proportion OD One has confidence that the sample proportion is equal to the population proportion
One can have 90% confidence that the interval from the lower bound (0.021) to the upper bound (0.033) actually contains the true value of the population proportion of adverse reactions. Option C is correct.
To construct the confidence interval for the proportion of adverse reactions, we will use the sample data and the provided confidence level of 90%.
a) The best point estimate of the population proportion p is the sample proportion of adverse reactions. We calculate it by dividing the number of patients who developed adverse reactions (130) by the total number of patients treated with the drug (4731):
p = 130 / 4731 ≈ 0.027
b) The margin of error (E) can be calculated using the formula:
[tex]E = z\times \sqrt{\dfrac{\hat p \times (1 - \hat p) }{ n}}[/tex]
where z is the critical value corresponding to the desired confidence level, p is the sample proportion, and n is the sample size.
Since the confidence level is 90%, we need to find the critical value associated with a 95% confidence level (since it's a two-tailed test). This critical value is approximately 1.645.
[tex]E = 1.645 \times \sqrt{\dfrac{(0.027 \times (1 - 0.027) }{ 4731}} \\E =0.006[/tex]
c) To construct the confidence interval, we use the formula:
Confidence interval = p ± E
Substituting the values, we get:
Confidence interval = 0.027 ± 0.006
The lower bound of the confidence interval is obtained by subtracting the margin of error from the point estimate:
Lower bound = 0.027 - 0.006 ≈ 0.021 (rounded to three decimal places)
The upper bound of the confidence interval is obtained by adding the margin of error to the point estimate:
Upper bound = 0.027 + 0.006 ≈ 0.033 (rounded to three decimal places)
Therefore, the 90% confidence interval for the proportion of adverse reactions is approximately 0.021 to 0.033.
d) The correct interpretation of the confidence interval is:
One can have 90% confidence that the interval from the lower bound (0.021) to the upper bound (0.033) actually contains the true value of the population proportion of adverse reactions." (Option C)
To know more about confidence intervals follow
https://brainly.com/question/31584043
#SPJ4
please answer as soon as possible. thank you
Evaluate the line integral (r+2y)dr + (r - y)dy along C:r = (0 ≤ t ≤n/4). 2cost, y4sint Select one: 01 OT 0 -
The line integral ∫[(r+2y)dr + (r - y)dy] along the curve C, defined by r = (2cos(t), 4sin(t)), where 0 ≤ t ≤ π/4, evaluates to π.
To evaluate the line integral ∫[(r+2y)dr + (r - y)dy] along the curve C given by r = (2cos(t), 4sin(t)), where 0 ≤ t ≤ π/4, we need to parameterize the curve and then integrate the given expression.
Let's start by expressing x and y in terms of t:
x = 2cos(t)
y = 4sin(t)
Now, let's find the differentials dx and dy:
dx = -2sin(t)dt
dy = 4cos(t)dt
Substituting these values into the line integral, we get:
∫[(r+2y)dr + (r - y)dy] = ∫[(2cos(t) + 2(4sin(t)))(-2sin(t)dt) + (2cos(t) - 4sin(t))(4cos(t)dt)]
Simplifying the expression, we have:
∫[(-4sin(t)cos(t) + 8sin^2(t) - 8sin(t)cos(t) + 8cos^2(t))dt]
= ∫[8(cos^2(t) - sin(t)cos(t) + sin^2(t))dt]
= ∫[8dt]
= 8t
Now, we evaluate the integral from t = 0 to t = π/4:
∫[8t] = [4t^2] evaluated from 0 to π/4
= 4(π/4)^2 - 4(0)^2
= π
Therefore, the value of the line integral along the curve C is π.
To learn more about line integral click here
brainly.com/question/29850528
#SPJ11
Identify the asymptotes of the hyperbola with equation (x - 2)^2 / 81 - (y + 2)^2 / 4 = 1
The asymptotes of the hyperbola are y = -2 + (2/9) * (x - 2) and y = -2 - (2/9) * (x - 2).
How to identify hyperbola asymptotes?To identify the asymptotes of the hyperbola with equation (x - 2)² / 81 - (y + 2) ² / 4 = 1 / 4 = 1, we can examine the standard form of a hyperbola equation:
[(x - h) ² / a ²] - [(y - k) ² / b ²] = 1
The asymptotes of a hyperbola can be determined using the formulas:
y = k ± (b / a) * (x - h)
Comparing the given equation to the standard form, we have:
h = 2, k = -2, a ² = 81, b ² = 4
Calculating the values:
a = √81 = 9
b = √4 = 2
Substituting these values into the formula for the asymptotes:
y = -2 ± (2 / 9) * (x - 2)
Therefore, the asymptotes of the hyperbola are given by the equations:
y = -2 + (2 / 9) * (x - 2)
y = -2 - (2 / 9) * (x - 2)
Learn more about hyperbola
brainly.com/question/19989302
#SPJ11
Find all values of x (if any) where the tangent line to the graph of the function is horizontal.
y = x^3 - 12x + 2
The values of x where the tangent line to the graph of the function y = x^3 - 12x + 2 is horizontal are x = 2 and x = -2.
How to find horizontal tangent lines?To find the values of x where the tangent line to the graph of the function y = x^3 - 12x + 2 is horizontal, we need to find the points on the graph where the derivative of the function is equal to zero.
First, let's find the derivative of the function with respect to x:
dy/dx = 3x^2 - 12
Next, set the derivative equal to zero and solve for x:
3x^2 - 12 = 0
Divide both sides of the equation by 3:
x^2 - 4 = 0
Factor the quadratic equation:
(x - 2)(x + 2) = 0
Setting each factor equal to zero:
x - 2 = 0 or x + 2 = 0
Solving for x:
x = 2 or x = -2
Therefore, the values of x where the tangent line to the graph of the function is horizontal are x = 2 and x = -2.
Learn more about tangent line
brainly.com/question/23416900
#SPJ11
Find the side indicated by the variable. Round to the nearest tenth. 17 degree, 7 hypotenuse, 90degree angle in the triangle
The length of the side indicated by the variable is 6.59 units
To find the side indicated by the variable in the given triangle, we can use the trigonometric function cosine.
Given:
Angle = 17 degrees
Hypotenuse = 7 units
90-degree angle (right angle)
We need to find the length of one of the other sides in the triangle.
Using the cosine function:
cos(17 degrees) = adjacent side / hypotenuse
We can rearrange the formula to solve for the adjacent side:
adjacent side = hypotenuse ×cos(17 degrees)
Substituting the values into the equation:
adjacent side = 7 × cos(17 degrees)
adjacent side = 6.59
Therefore, the length of the side indicated by the variable is 6.59 units
To learn more on trigonometry click:
https://brainly.com/question/25122835
#SPJ1
The number of problems on all math exams are normal distributed. What is the probability a randomly selected math exam has fewer than 15 questions if the mean is 20 questions with a standard deviation of 2.5? Use the empirical rule. Enter your answer as a percent rounded to two decimal places if necessary.
Previous question
The probability of less than 15 questions in a randomly chosen maths test is 2.28%, rounded to two decimal places.
According to the empirical rule,
68% of the data falls within one standard deviation of the mean,
95% falls within two standard deviations of the mean,
And 99.7% falls within three standard deviations of the mean.
Since we want to find the probability of a math exam having fewer than 15 questions,
Which is more than one standard deviation below the mean,
we have to find the proportion of the data that falls outside of one standard deviation below the mean.
To do this, we first need to standardize the value of 15 using the formula ⇒ z = (x - mu) / sigma,
where x is the value we want to standardize,
mu is the mean, and sigma is the standard deviation.
In this case,
⇒ z = (15 - 20) / 2.5
= -2.
Now, we can look up the proportion of data that falls beyond two standard deviations below the mean in a standard normal distribution table.
This is equivalent to finding the area to the left of z = -2,
which is approximately 0.0228.
Therefore, the probability of a randomly selected math exam having fewer than 15 questions is 2.28%, rounded to two decimal places.
Learn more about the probability visit:
https://brainly.com/question/13604758
#SPJ4
The system of differential equations dx/dt = 0.4x - 0.002x^2 - 0.001xy dy/dt = 0.5y - 0.001y^2 - 0.004xy is a model for the populations of two species. (a) Does the model describe cooperation, or competition, or a predator-prey relationship? cooperation competition predator-prey relationship
Based on the given system of differential equations this model describes a predator-prey relationship.
Based on the given system of differential equations:
dx/dt = 0.4x - 0.002x² - 0.001xy
dy/dt = 0.5y - 0.001y² - 0.004xy
This model describes a predator-prey relationship. The reason is that the interaction term (-0.001xy and -0.004xy) in both equations is negative, meaning that as one population (x or y) increases, it negatively impacts the growth rate of the other population. This type of interaction is characteristic of a predator-prey relationship, where one species feeds on the other, resulting in a decrease in the prey population and an increase in the predator population.
To know more about Equation visit:
https://brainly.com/question/29174899
#SPJ11
Watch help video The velocity of an object moving in a straight line, in kilometers per hour, can be modeled by the function v(t), where t is measured in hours. The position of the object when t = 2 is 55 kilometers. Selected values of v(t) are shown in the table below. Use a linear approximation when t = 2 to estimate the position of the object at time t = 2.2. Use proper units. t 0 2 5 7 13 18 5 4 5 2 u(t) 8 2 6 9 Submit Answer Answer: attempt 1 out of hours hours per kilometer hours per kilometer Ilometers Kilometers per hour kilometers per hour Privacy Policy Terms of Service
To estimate the position of the object at time t = 2.2 using a linear approximation, we can use the slope of the line connecting the two closest known points, which are (t, u(t)) = (2, 55) and (t, u(t)) = (5, 6).
The slope of the line is given by:
m = (u(t₂) - u(t₁)) / (t₂ - t₁)
Substituting the values:
m = (6 - 55) / (5 - 2) = -49 / 3
Now, we can use the point-slope form of a line to find the equation of the line:
u(t) - u(t₁) = m(t - t₁)
Substituting the values:
u(t) - 55 = (-49/3)(t - 2)
Now, we can substitute t = 2.2 into the equation to estimate the position of the object:
u(2.2) - 55 = (-49/3)(2.2 - 2)
Simplifying:
u(2.2) - 55 = (-49/3)(0.2)
u(2.2) - 55 = -49/15
To find the estimated position of the object at t = 2.2, we add the value to the initial position at t = 2:
u(2.2) = -49/15 + 55
Calculating the result:
u(2.2) ≈ 53.733
Therefore, the estimated position of the object at t = 2.2 is approximately 53.733 kilometers.
To know more about Linear approximation click on the link below:
brainly.com/question/1621850#
#SPJ11
What is (are) the solution(s) of the equation x2=3664 ? Responses
The two solutions of the quadratic equation are:
x = 60.53 and x = -60.5
How to find the solutions of the quadratic equation?Here we have a simple quadratic equation where we don't have a linear term, it is:
x² = 3664
To solve this, we just need to apply the square root in both sides, we will get:
x = ±√3664
We have the plus/minus sign because of the rule of signs.
Then the solutions are:
x = ±60.53
These are the two solutions of the quadratic equation.
Learn more about square roots at:
https://brainly.com/question/428672
#SPJ1
The quadratic equation has two solutions x = 60.53 and x = -60.5
How do you find the quadratic equation's solutions?The following is a simple quadratic equation without a linear term:
x² = 3664
To solve this, we simply multiply both sides by the square root, yielding:
x = ±√3664
Because of the rule of signs, we have the plus/minus sign.
The solutions are as follows:
x = ±60.53
These are the two quadratic equation solutions.
More information regarding square roots can be found at: brainly.com/question/428672
#SPJ1
a mattress store is having a sale all items are for sale are discounted 15% if william is buying a bedspread of 38.25 what is the cost initially
To find the initial cost of the bedspread before the 15% discount, we can use the formula:
Initial cost = Final cost / (1 - Discount rate)
In this case, the final cost is $38.25, and the discount rate is 15% or 0.15.
Initial cost = $38.25 / (1 - 0.15)
Initial cost = $38.25 / 0.85
Initial cost ≈ $45
Therefore, the initial cost of the bedspread before the 15% discount is approximately $45.
true or false? explain your answer. if ! ! < < , then cos ! ! < 0.
The given statement "If π /2 < θ < π, then cos θ /2 < 0" is False. We are considering an angle in the second quadrant of the unit circle. In the second quadrant, the cosine function is negative, which means cos(θ/2) is also negative.
Given: π/2 < θ < π (This means θ lies in the second quadrant)
Let's consider θ/2:
θ/2 = (π/2)/2 = π/4
Now, let's evaluate cos(θ/2):
cos(π/4) = √2/2 (since cos(π/4) = √2/2)
We need to determine if cos(θ/2) is less than zero:
√2/2 > 0
Therefore, the statement "cos(θ/2) < 0" is false.
In conclusion, the statement is false because in the second quadrant, cos(θ/2) is positive, not negative.
To know more about quadrant:
https://brainly.com/question/26426112
#SPJ4
--The given question is incomplete, the complete question is given below " True or False? Explain your answer. If π /2 < θ < π, then cos θ /2 < 0."--
1
This piecewise function represents the Social Security taxes for 2016. How much did
Mindy pay in Social Security tax if she earned $109,500 in 2016?
Mindy pay $ 6789 in Social Security tax if she earned $ 109,500 in 2016.
It is given that the piecewise function represents the Social Security taxes for 2016.
f(x) = { 0.062 x when 0 < x < 111,800
= { $ 7,621.60 when x > 111,800
We need to find Mindy's security tax if she earned $109,500 in 2016.
Since 102,000 lies in 0 < x < 111,800 , therefore
f(x) = 0.062 x
Put x = 109,500
f(x) = 0.062 × 109,500
= 6789
Therefore, Mindy pay $ 6789 in Social Security tax if she earned $ 109,500 in 2016.
Learn more about piecewise function here
https://brainly.com/question/17398784
#SPJ4
Given question is incomplete, the complete question is below
This piecewise function represents the Social Security taxes for 2016. How much did Mindy pay in Social Security tax if she earned $109,500 in 2016?
f(x) = { 0.062 x when 0 < x < 111,800
= { $ 7,621.60 when x > 111,800
Which of the following is a parameterization of the sphere of radius 2 centered at the origin that lies in the first octant and lies outside of the cylinder x^2 +y^2=1?
A parameterization of the sphere of radius 2 centered at the origin that lies in the first octant and outside of the cylinder x^2 + y^2 = 1 is: x = 2sinθcosϕ, y = 2sinθsinϕ, z = 2cosθ where θ ranges from 0 to π/2 and ϕ ranges from 0 to π/2.
The parameterization given is in spherical coordinates. In this parameterization, θ represents the polar angle measured from the positive z-axis (ranging from 0 to π/2), and ϕ represents the azimuthal angle measured from the positive x-axis (ranging from 0 to π/2).
For the given parameterization, when θ and ϕ are restricted to the specified ranges, the resulting points lie in the first octant (x, y, and z are all positive). Additionally, the points lie on the surface of the sphere of radius 2 centered at the origin. This is because the x, y, and z coordinates are determined by the trigonometric functions of θ and ϕ, scaled by the radius 2.
By restricting ϕ to the range from 0 to π/2, we ensure that the points lie outside of the cylinder x^2 + y^2 = 1, which represents a cylinder of radius 1 centered along the z-axis. This restriction ensures that the points lie in the first octant and do not intersect the cylinder.
To know more about sphere,
https://brainly.com/question/31852422
#SPJ11
2) Given: Mean = .34 and Standard Deviation = .08, Calculate the margin of error.
To calculate the margin of error, you need to determine the critical value associated with the desired level of confidence. The margin of error is then obtained by multiplying the critical value by the standard deviation.
Let's assume you want to calculate the margin of error for a 95% confidence level. For a normal distribution, the critical value corresponding to a 95% confidence level is approximately 1.96.
Margin of Error = Critical Value * Standard Deviation
Using the given values:
Standard Deviation = 0.08
For a 95% confidence level:
Critical Value = 1.96
Margin of Error = 1.96 * 0.08
Calculating the margin of error:
Margin of Error = 0.1568
Therefore, the margin of error is approximately 0.1568
Find the area of the region enclosed by one loop of the curve r = 3 cos (5θ). Area = ___
The area enclosed by one loop of the curve r = 3 cos(5θ) is (9π/2).
How to find the area of the region enclosed by one loop of the polar curve r = 3 cos(5θ)?To find the area of the region enclosed by one loop of the polar curve r = 3 cos(5θ), we can use the formula for the area bounded by a polar curve:
A = (1/2) ∫[θ1, θ2] (r^2) dθ
In this case, we need to find the values of θ1 and θ2 that correspond to one complete loop of the curve. The curve r = 3 cos(5θ) completes one loop when θ goes from 0 to 2π.
So, we have:
θ1 = 0
θ2 = 2π
Now, we can calculate the area:
A = (1/2) ∫[0, 2π] (3 cos(5θ))^2 dθ
Simplifying the integral:
A = (1/2) ∫[0, 2π] 9 cos^2(5θ) dθ
Using the identity cos^2(θ) = (1/2)(1 + cos(2θ)), we have:
A = (1/2) ∫[0, 2π] 9 * (1/2)(1 + cos(10θ)) dθ
Simplifying further:
A = (9/4) ∫[0, 2π] (1 + cos(10θ)) dθ
Integrating:
A = (9/4) [θ + (1/10)sin(10θ)] evaluated from 0 to 2π
Evaluating the definite integral at the limits:
A = (9/4) [2π + (1/10)sin(20π) - (1/10)sin(0)]
Since sin(0) = sin(20π) = 0, the equation simplifies to:
A = (9/4) * 2π
Simplifying further:
A = 9π/2
Therefore, the area enclosed by one loop of the curve r = 3 cos(5θ) is (9π/2).
Learn more about area
brainly.com/question/30307509
#SPJ11
if ⃗a ·⃗b = √3 and ⃗a ×⃗b = ⟨1, 2, 2⟩, find the angle between ⃗a and ⃗b
The angle between [tex]\(\vec{a}\) and \(\vec{b}\) is \(60^\circ\).[/tex]
To find the angle between two vectors[tex]\(\vec{a}\) and \(\vec{b}\)[/tex], we can use the dot product formula:
[tex]\(\vec{a} \cdot \vec{b} = |\vec{a}| |\vec{b}| \cos(\theta)\),[/tex]
where [tex]\(|\vec{a}|\) and \(|\vec{b}|\)[/tex] are the magnitudes of the vectors and[tex]\(\theta\)[/tex]is the angle between them.
Given that [tex]\(\vec{a} \cdot \vec{b} = \sqrt{3}\),[/tex] we can rewrite the equation as:
[tex]\(\sqrt{3} = |\vec{a}| |\vec{b}| \cos(\theta)\).[/tex]
We are also given that [tex]\(\vec{a} \times \vec{b} = \langle 1, 2, 2 \rangle\),[/tex]which represents the cross product of the vectors.
The magnitude of the cross product is given by:
[tex]\(|\vec{a} \times \vec{b}| = |\vec{a}| |\vec{b}| \sin(\theta)\).[/tex]
Substituting the given values, we have:
[tex]\(|\vec{a} \times \vec{b}| = |\vec{a}| |\vec{b}| \sin(\theta) = |\langle 1, 2, 2 \rangle| = \sqrt{1^2 + 2^2 + 2^2} = \sqrt{9} = 3\).[/tex]
We can rearrange the equation to solve for [tex]\(|\vec{a}| |\vec{b}| \sin(\theta)\):\(3 = |\vec{a}| |\vec{b}| \sin(\theta)\).[/tex]
Now, we have two equations:
[tex]\(\sqrt{3} = |\vec{a}| |\vec{b}| \cos(\theta)\),\(3 = |\vec{a}| |\vec{b}| \sin(\theta)\).[/tex]
To eliminate the magnitudes [tex]\(|\vec{a}|\) and \(|\vec{b}|\)[/tex], we can square both equations and add them together:
[tex]\((\sqrt{3})^2 + 3^2 = (|\vec{a}| |\vec{b}|)^2 (\cos^2(\theta) + \sin^2(\theta))\)[/tex].
Simplifying, we get:
[tex]\(3 + 9 = (|\vec{a}| |\vec{b}|)^2\).\(12 = (|\vec{a}| |\vec{b}|)^2\).[/tex]
Taking the square root of both sides:
[tex]\(\sqrt{12} = |\vec{a}| |\vec{b}|\).\(\sqrt{12} = |\vec{a}| |\vec{b}| = |\vec{a}| |\vec{b}| \sqrt{\cos^2(\theta) + \sin^2(\theta)}\).[/tex]
Since [tex]\(\cos^2(\theta) + \sin^2(\theta) = 1\)[/tex], we have:
[tex]\(\sqrt{12} = |\vec{a}| |\vec{b}| \cdot 1\).\(\sqrt{12} = |\vec{a}| |\vec{b}|\).[/tex]
Now, we can substitute this back into the first equation:
[tex]\(\sqrt{3} = \sqrt{12} \cos(\theta)\).[/tex]
Simplifying, we get:
[tex]\(\cos(\theta) = \frac{\sqrt{3}}{\sqrt{12}} = \frac{\sqrt{3}}{2\sqrt{3}} = \frac{1}{2}\).[/tex]
To find the angle [tex]\(\theta\)[/tex], we take the inverse cosine (
arc cosine) of [tex]\(\frac{1}{2}\):[/tex]
[tex]\(\theta = \cos^{-1}\left(\frac{1}{2}\right)\).[/tex]
Using the unit circle or trigonometric identities, we find that[tex]\(\theta = \frac{\pi}{3}\) or \(60^\circ\).[/tex]
Therefore, the angle between [tex]\(\vec{a}\) and \(\vec{b}\) is \(60^\circ\).[/tex]
To learn more about angle from the given link
https://brainly.com/question/28394984
#SPJ4
Arrange the steps in correct order to solve the congruence 2x = 7 (mod 17) using the inverse of 2 modulo 17, which is 9. Rank the options below. 9 is an inverse of 2 modulo 17. The given equation is 2x = 7 (mod 17). Multiplying both sides of the equation by 9, we get x = 9.7 (mod 17). Since 63 mod 17 = 12, the solutions are all integers congruent to 12 modulo 17, such as 12, 29, and -5.
63 mod 17 = 12, the solutions are all integers congruent to 12 modulo 17, such as 12, 29, and -5.
The given equation is 2x = 7 (mod 17).
9 is an inverse of 2 modulo 17.
Multiplying both sides of the equation by 9, we get x = 9.7 (mod 17).
Since 63 mod 17 = 12, the solutions are all integers congruent to 12 modulo 17, such as 12, 29, and -5.
Correct order:
The given equation is 2x = 7 (mod 17).
9 is an inverse of 2 modulo 17.
Multiplying both sides of the equation by 9, we get x = 9.7 (mod 17).
To know more about integers visit:
brainly.com/question/15276410
#SPJ11
Many species are made up of several small subpopulations that occasionally go extinct but that are subsequently recolonized. The entire collection of subpopulations is referred to as a metapopulation. One way to model this phenomenon is to keep track only of the fraction of subpopulations that are currently extant. Suppose p(t) is the fraction of subpopulation that are extant at time t. The Levins model states that p(c) obeys the following differential equation: dp cp(1-p)- ep dt where c and e are positive constants reflecting the colonization and extinction rates respectively (a) What are the equilibria of this model in terms of the parameters? (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.) (b) What are the conditions on the parameters for the nonzero equilibrium found in part (a) to lie between 0 and 1? e>c e=c e< c (c) What are the conditions on the parameters for the nonzero equilibrium found in part (a) to be locally stable? esc e
(a) The equilibria of the model can be found by setting dp/dt = 0 and solving for p. From the given differential equation, we have cp(1-p) - ep = 0. Rearranging this equation, we get cp - cp^2 - ep = 0. Factoring out p, we have p(cp - cp - e) = 0. Simplifying further, we find that the equilibria are p = 0 and p = (c - e)/c.
(b) To ensure that the nonzero equilibrium p = (c - e)/c lies between 0 and 1, we need the fraction to be positive and less than 1. This implies that c - e > 0 and c > e.
(c) The conditions for the nonzero equilibrium to be locally stable depend on the sign of the derivative dp/dt at that equilibrium. Taking the derivative dp/dt and evaluating it at p = (c - e)/c, we find dp/dt = (c - e)(1 - (c - e)/c) - e = (c - e)(e/c). For the equilibrium to be locally stable, we require dp/dt < 0. Therefore, the condition for local stability is (c - e)(e/c) < 0, which can be simplified to e < c.
In conclusion, the equilibria of the Levins model are p = 0 and p = (c - e)/c. The nonzero equilibrium lies between 0 and 1 when c > e, and it is locally stable when e < c.
Learn more about differential equation here:
brainly.com/question/25731911
#SPJ11