n homeroom, 3 of the 16 girls have red hair and 2 of the 15 boys have red hair. what is the probability of selecting a boy or a red-haired person as homeroom representative to student council

Answers

Answer 1

To calculate the probability of selecting a boy or a red-haired person as a homeroom representative to student council, we need to find the probability of each event and then use the formula P(A or B) = P(A) + P(B) - P(A and B).

There are 31 students in total (16 girls + 15 boys). The probability of selecting a boy is 15/31.

There are 5 red-haired students (3 girls + 2 boys). The probability of selecting a red-haired person is 5/31.

However, we need to account for the overlap between boys and red-haired students. There are 2 red-haired boys, so the probability of selecting a red-haired boy is 2/31.

Now we can use the formula: P(boy or red-haired) = P(boy) + P(red-haired) - P(boy and red-haired) = (15/31) + (5/31) - (2/31) = 18/31.

So, the probability of selecting a boy or a red-haired person as a homeroom representative to student council is 18/31.

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Related Questions

6) Practice: Using Visual Cues Label each part of the diagram. Then use your labels to complete the sentences. Square Root Notation √6 1. The expression √ means "the of b". 2. The exponent 1 symbol (√) stands for the 3. The number or expression under the radical symbol is called the​

Answers

1. The expression √b means "the square root of b".

2. The radical symbol (√) stands for the exponent 1/2.

3. The number or expression under the radical symbol is called the radicand.

What is radicand?

A radicand is the number or expression underneath a radical symbol (√). It is the number or expression that is being operated on by the root. The square root of the radicand is the result of the operation.

The expression √6 represents the square root of 6. This is the value of x that, when multiplied with itself, results in 6.

The square root of 6 is equal to 2.44948974, which is the positive solution to the equation x² = 6.

The radical symbol (√) indicates that the expression is a root and the number or expression under the radical symbol is called the radicand, which is 6 in this case.

The exponent of the radical symbol is 1/2, which implies that the expression is a square root.

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Which equation could be solved using this application of the quadratic formula?
-(12) ± √(12)²-4(2)(-9)
2(2)
O 12x² - 4x + 13 = 4
12x² - 4x + 4 = 13
2x² + 12x + 13 = 4
2x² + 12x + 4 = 13
x =

Answers

An equation that could be solved using this application of the quadratic formula include the following: D. 2x² + 12x + 4 = 13.

What is a quadratic equation?

In Mathematics and Geometry, a quadratic equation can be defined as a mathematical expression that can be used to define and represent the relationship that exists between two or more variable on a graph.

In Mathematics, the standard form of a quadratic equation is represented by the following equation;

ax² + bx + c = 0

Mathematically, the quadratic formula is modeled or represented by this mathematical equation:

[tex]x = \frac{-b\; \pm \;\sqrt{b^2 - 4ac}}{2a}[/tex]

For the given quadratic equation 2x² + 12x + 4 = 13, we have:

2x² + 12x + 4 = 13

2x² + 12x + 4 - 13 = 0

2x² + 12x - 9 = 0

By substituting, we have;

[tex]x = \frac{-(12)\; \pm \;\sqrt{(12)^2 - 4(2)(-9)}}{2(2)}[/tex]

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determine the failure rate for a 100-hr test of 11 samples, where 3 items failed at 35, 64 and 72 hrs., respectively.

Answers

The failure rate for the 100-hour test with 11 samples is 2.73%. It can be expressed as the proportion of failed samples over the total time of the test and the number of samples.

How to determine the failure rate?

To determine the failure rate for a 100-hr test of 11 samples, where 3 items failed at 35, 64, and 72 hours, respectively, we can use the following formula:

Failure rate = (Number of failures / Total time of the test) * (1 / Number of samples)

Number of failures = 3

Total time of the test = 100 hours

Number of samples = 11

So, the failure rate would be:

Failure rate = (3 / 100) * (1 / 11) = 0.0273 or 2.73%

Therefore, the failure rate for this 100-hour test with 11 samples is 2.73%.

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Find the value of ‘x’
x =

Answers

The value of x, in the image given is calculated by applying the intersecting chords theorem, which is: x = 16.

What is the Intersecting Chords Theorem?

The Intersecting Chords Theorem, also known as the Ptolemy's Theorem, states that in a circle, if two chords intersect, then the product of the lengths of the segments of one chord is equal to the product of the lengths of the segments of the other chord.

In mathematical terms, if two chords, AB and CD, intersect at point E inside a circle, then:

AE × EB = CE × ED

Applying the theorem, we have:

5(x) = (x - 6)8

5x = 8x - 48

5x - 8x = -48

-3x = -48

x = 16

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Leah uses 20 ounces of beeswax to make 6 identical small candles. How many ounces of beeswax does leah need to make 15 more small candles

Answers

The ounces of  beeswax needed by Leah to make 15 more small candles is equal to 49.95 ounces.

Let us consider 'x' be the ounces of beeswax required by Leah to make 15 candles.

To make 6 small candles, Leah uses 20 ounces of beeswax.

So, to make one small candle,

Ounces of beeswax used by Leah ,

= 20 ounces / 6 candles

= 3.33 ounces/candle (rounded to two decimal places)

To make 15 more small candles,

Ounces of beeswax Leah will need is equals to,

⇒ x = 15 candles x 3.33 ounces/candle

⇒ x = 49.95 ounces (rounded to two decimal places)

Therefore, Leah needs 49.95 ounces of beeswax to make 15 more small candles.

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what is the ratio of the area of triangle to the area of triangle ? express your answer as a common fraction.

Answers

Thus, the ratio of the area of larger triangle to the area of smaller triangle

is found as 5:1.

Explain about the ratios:

An instrument for comparing the sizes of two or more quantities in proportion to one another is called a ratio. A list of the structured equivalent ratios of every given ratio is called a ratio table. By multiplying as well as dividing the 2 terms of such a ratio by an identical number, equivalent ratios can be created.

Given data:

Dimension of  larger triangle: base B = 10 cm, Height H = 5 cm.Dimension of  smaller triangle : base b = 5 cm, Height H = 2 cm.

Area of triangle = 1/2* base * height

Ratios:

area of larger triangle / area of smaller triangle = (1/2*B*H) / (1/2*b*h)

area of larger triangle / area of smaller triangle = B*H / b*h

area of larger triangle / area of smaller triangle = 10*5 / 5*2

area of larger triangle / area of smaller triangle = 50 / 10

area of larger triangle / area of smaller triangle = 5/ 1 = 5:1

Thus, the ratio of the area of larger triangle to the area of smaller triangle

is found as 5:1.

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Complete question:

what is the ratio of the area of larger triangle to the area of smaller triangle ? express your answer as a common fraction.

Dimension of  larger triangle: base B = 10 cm, Height H = 5 cm.

Dimension of  smaller triangle : base b = 5 cm, Height H = 2 cm.

The use of heuristics rather than algorithms is most likely to _____.
A. yield more accurate solutions to problems
B. save time in arriving at solutions to problems
C. minimize the overconfidence phenomenon
D. involve greater reliance on language skills

Answers

B. save time in arriving at solutions to problems. Heuristics are problem-solving shortcuts or rules of thumb that can save time when arriving at solutions to problems.

The use of heuristics rather than algorithms is most likely to save time in arriving at solutions to problems. Heuristics are mental shortcuts or rules of thumb that are used to solve problems quickly and efficiently, whereas algorithms are step-by-step procedures for solving problems. While algorithms may produce more accurate solutions, they can be time-consuming to apply. Heuristics, on the other hand, allow for quick problem-solving and are often based on our language skills and prior knowledge. However, relying too heavily on heuristics can sometimes lead to errors or the overconfidence phenomenon.


They might not always yield the most accurate solutions compared to algorithms, which are step-by-step, systematic procedures that guarantee a correct solution. Heuristics usually rely less on language skills and do not necessarily minimize the overconfidence phenomenon.

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Heuristics are mental shortcuts or rules of thumb that people use to make decisions or solve problems quickly and efficiently.

B. save time in arriving at solutions to problems . The correct answer is:

Heuristics are mental shortcuts or rules of thumb that people use to make decisions or solve problems quickly and efficiently. They are simple and often automatic strategies that allow individuals to make judgments or decisions without engaging in a lengthy, deliberate, and systematic process of problem-solving.

One of the main advantages of using heuristics is that they can save time in arriving at solutions to problems. Instead of analyzing all available information and considering all possible alternatives, heuristics allow individuals to quickly narrow down options and make decisions based on simplified cognitive processes. This can be especially useful in situations where time is limited or when individuals need to make decisions on the spot.

However, heuristics are not always foolproof and can sometimes lead to errors or biases in decision-making.

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Peter needs to borrow $10,000 to repair his roof. He will take out a 317-loan on April 15th at 4% interest from the bank. He will make a payment of $3,500 on October 12th and a payment of $2,500 on January 11th.

a) What is the due date of the loan?

b) Calculate the interest due on October 12th and the balance of the loan after the October 12th payment.

c) Calculate the interest due on January 11th and the balance of the loan after the January 11th pa payment.

d) Calculate the final payment (interest + principal) Peter must pay on the due date.

Please only serious answers ​

Answers

Answer:

A. February 26th

B. $3,500 - Balance ≈ $6,697.26

C. $2,500 - Balance ≈ $4,263.46

D. $4,284.81

Step-by-step explanation:

a) What is the due date of the loan?

The loan term is given as 317 days, and the loan starts on April 15th. To find the due date, we will add 317 days to April 15th.

April 15th + 317 days = April 15th + (365 days - 48 days) = April 15th + 1 year - 48 days

Subtracting 48 days from April 15th, we get:

Due date = February 26th (of the following year)

b) Calculate the interest due on October 12th and the balance of the loan after the October 12th payment.

First, we need to calculate the number of days between April 15th and October 12th:

April (15 days) + May (31 days) + June (30 days) + July (31 days) + August (31 days) + September (30 days) + October (12 days) = 180 days

Now, we will calculate the interest for 180 days:

Interest = Principal × Interest Rate × (Days Passed / 365)

Interest = $10,000 × 0.04 × (180 / 365)

Interest ≈ $197.26

Peter will make a payment of $3,500 on October 12th. So, we need to find the balance of the loan after this payment:

Balance = Principal + Interest - Payment

Balance = $10,000 + $197.26 - $3,500

Balance ≈ $6,697.26

c) Calculate the interest due on January 11th and the balance of the loan after the January 11th payment.

First, we need to calculate the number of days between October 12th and January 11th:

October (19 days) + November (30 days) + December (31 days) + January (11 days) = 91 days

Now, we will calculate the interest for 91 days:

Interest = Principal × Interest Rate × (Days Passed / 365)

Interest = $6,697.26 × 0.04 × (91 / 365)

Interest ≈ $66.20

Peter will make a payment of $2,500 on January 11th. So, we need to find the balance of the loan after this payment:

Balance = Principal + Interest - Payment

Balance = $6,697.26 + $66.20 - $2,500

Balance ≈ $4,263.46

d) Calculate the final payment (interest + principal) Peter must pay on the due date.

First, we need to calculate the number of days between January 11th and February 26th:

January (20 days) + February (26 days) = 46 days

Now, we will calculate the interest for 46 days:

Interest = Principal × Interest Rate × (Days Passed / 365)

Interest = $4,263.46 × 0.04 × (46 / 365)

Interest ≈ $21.35

Finally, we will calculate the final payment Peter must pay on the due date:

Final payment = Principal + Interest

Final payment = $4,263.46 + $21.35

Final payment ≈ $4,284.81

What are three distances that are equivalent to 1/2 mile.

Answers

Three distances that are equivalent to 1/2 mile are:

880 yards

1,609.34 meters

2,640 feet

Find the mean, median, and mode for the data set. Express your answers as decimals rounded to the nearest tenth, if necessary.
13, 14, 15, 17, 18, 19, 19, 19, 20, 20, 21, 21, 21, 21, 22, 22, 23, 23, 24

Answers

The median is 20, the mean is 19.57 and the mode is 21

Keiko paid $15. 84 for a 7. 48 - kg bag of dog food. A few weeks later, she paid $16. 58 for a 7. 94 - kg bag at a different store. Find the unit price for each bag

Answers

The unit price for the first bag is $2.12 per kilogram and the unit price for the second bag is $2.09 per kilogram.

To find the unit price, we need to divide the total cost by the weight of the bag.

For the first bag

Unit price = Total cost / Weight

Unit price = $15.84 / 7.48 kg

Unit price = $2.12/kg

Therefore, the unit price for the first bag is $2.12 per kilogram.

For the second bag

Unit price = Total cost / Weight

Substitute the values in the equation

Unit price = $16.58 / 7.94 kg

Unit price = $2.09/kg

Therefore, the unit price for the second bag is $2.09 per kilogram.

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a kite flying in the air has a 94- string attached to it, and the string is pulled taut. the angle of elevation of the kite is . find the height of the kite. round your answer to the nearest tenth.

Answers

The height of the kite is approximately 68.4 ft.

To solve the problem, we can use trigonometry. We know that the string is the hypotenuse of a right triangle, with the height of the kite as one of the legs. The angle of elevation, which is the angle between the string and the ground, is also given. We can use the tangent function to find the height of the kite:

tan(46°) = height / 94

Solving for height, we get:

height = 94 * tan(46°)

Using a calculator, we get:

height ≈ 68.4 ft

Therefore, the height of the kite is approximately 68.4 ft.

We use the given angle of elevation and the length of the string to set up a right triangle with the height of the kite as one of the legs. Then, we use the tangent function to relate the angle to the height of the kite. Finally, we solve for the height using a calculator and round to the nearest tenth as requested.

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Complete Question:

A kite flying in the air has a 94-ft string attached to it, and the string is pulled taut. The angle of elevation of the kite is 46 °. Find the height of the kite. Round your answer to the nearest tenth.

52 no one can win more than one prize? multiple choice 16,129,423 16,497,400 15,281,283 16,300,400

Answers

The closest choice to the actual number of ways to choose 52 different winners out of 52 contestants is 16,497,400,

To solve this problem, we can use the formula for permutations, which is:

nPr = n! / (n - r)!

where n is the total number of objects (in this case, 52), and r is the number of objects we are choosing (in this case, the number of prizes, which is also 52).

Since no one can win more than one prize, we need to choose 52 different winners for the prizes. Therefore, the number of ways to do this is:

52P52 = 52! / (52 - 52)! = 52!

Using a calculator or computer program, we can find that 52! is approximately equal to 8.0658 × 10^67.

Therefore, the answer is 16,497,400, which is the closest choice to the actual number of ways to choose 52 different winners out of 52 contestants.

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for a math assignment, michelle rolls a set of three standard dice at the same time and notes the results of each trial. what is the total number of outcomes for each trial?

Answers

There are 216 possible outcomes for each trial of rolling three standard dice.

In probability theory, an outcome is defined as the result of a single experiment or trial. The total number of outcomes in a trial can be determined by the multiplication principle, which states that if there are m ways to do one thing, and n ways to do another, then there are m x n ways to do both.

In this case, Michelle is rolling three standard dice simultaneously, which means that there are six possible outcomes for each die. Therefore, the total number of outcomes for a single trial is calculated by multiplying the number of outcomes for each die. Using the multiplication principle, we get:

Number of outcomes for each die = 6

Total number of outcomes for a single trial = 6 x 6 x 6 = 216

It is important to note that not all outcomes are equally likely, and the probability of getting a specific outcome can be calculated by dividing the number of favorable outcomes by the total number of outcomes.

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Find the solution to the system of equations. Write the solution as an ordered pair. If there are no solutions, write 'no solutions'. If there are infinitely many, write 'infinitely many'.

y = −72
x + 11

7x + 2y = 20

Answers

The solution to the system of equations is (23, -72).

How to find system of equations ?

The first equation is y = -72, which means that whatever the value of x is, the value of y will always be -72.

Substituting y = -72 in the second equation, we get:

7x + 2(-72) = 20

Simplifying this equation, we get:

7x - 144 = 20

Adding 144 to both sides, we get:

7x = 164

Dividing both sides by 7, we get:

x = 23.428571...

So the solution to the system of equations is the ordered pair (x, y) = (23.428571..., -72).

However, we usually express solutions as ordered pairs of integers, so we can round x to the nearest integer to get:

(x, y) = (23, -72)

Therefore, the solution to the system of equations is (23, -72).

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what is the answer to this question? (please i need help)

Answers

Answer:

-5d + 5.5 < 17

-5d < 11.5

d > -2.3

A is the correct solution.

Graph the equation y=x2+4x-5 on the accompanying set of axes. You must plot 5 points including the roots and the vertex.

Answers

Answer:

Roots = (1, 0) and (-5, 0)

Vertex = (-2, -9)

Two additional points = (-4, -5) and (0, -5)

Step-by-step explanation:

The given equation y = x² + 4x - 5 is a quadratic equation with a positive leading coefficient. Therefore, the shape of the curve is a parabola that opens upwards.

The roots of a quadratic equation are the x-values that satisfy the equation y = 0. They are the points at which the curve crosses the x-axis.

To calculate the roots of the given equation, set it to zero and solve for x.

[tex]\begin{aligned}x^2+4x-5&=0\\x^2+5x-x-5&=0\\x(x+5)-1(x+5)&=0\\(x-1)(x+5)&=0\\\\\implies x-1&=0 \implies x=1\\\implies x+5&=0 \implies x=-5\end{aligned}[/tex]

Therefore, the roots of the equation are (1, 0) and (-5, 0).

The x-value of the vertex of a quadratic function in the form ax² + bx + c is -b/2a.

For the given equation y = x² + 4x - 5, a = 1 and b = 4.

To find the x-value of the vertex, substitute these values into the formula:

[tex]x_{\sf vertex}=\dfrac{-b}{2a}=\dfrac{-4}{2(1)}=-2[/tex]

To find the y-value of the vertex, substitute the x-value of the vertex into the given equation:

[tex]y_{\sf vertex}=(-2)^2+4(-2)-5=-9[/tex]

Therefore, the vertex is (-2, -9).

To find two other points on the curve, substitute two values of x into the equation.

[tex]\begin{aligned}x=-4 \implies y&=(-4)^2+4(-4)-5\\&=16-16-5\\&=0-5\\&=-5\end{aligned}[/tex]

[tex]\begin{aligned}x=0 \implies y&=(0)^2+4(0)-5\\&=0+0-5\\&=0-5\\&=-5\end{aligned}[/tex]

The axis of symmetry of a quadratic equation is the vertical line that divides the parabola into two mirror images. The x-value of the vertex is the axis of symmetry. Therefore, the axis of symmetry is x = -2.

To graph the given equation:

Plot the roots (1, 0) and (-5, 0).Plot the vertex (-2, -9).Plot two additional points (-4, -5) and (0, -5).Draw the axis of symmetry x = -2.Draw a parabola that is symmetrical about the axis of symmetry and passes through the plotted points.

Which statement about subnetting is correct?
A. Subnetting applies only to IPv4 networks, unless you are using classless interdomain routing.
B. Both IPv4 and IPv6 provide for subnetting, but the much larger IPv6 address field makes this a lot simpler to design and manage.
C. Subnetting in IPv4 involves the CIDR protocol, which runs at Layer 3; in IPv6, this protocol, and hence subnetting, is not used.
D. Because the subnet mask field is so much larger in IPv6, it is easier to subnet in this newer protocol stack than in IPv4.

Answers

The statement "Both IPv4 and IPv6 provide for subnetting, but the much larger IPv6 address field makes this a lot simpler to design and manage" is correct for subnetting.

Hence, the correct option is B.

In IPv4, subnetting involves dividing a network into smaller subnetworks using the Classless Inter-Domain Routing (CIDR) protocol at Layer 3, which allows for more efficient use of IP addresses. The subnet mask determines the network and host portions of the IP address.

IPv6 also supports subnetting, but uses a different approach called prefix notation, where the network and subnet are represented by a prefix length rather than a subnet mask. Since the address field in IPv6 is much larger than IPv4, there are more available addresses and therefore it is easier to subnet.

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HELP W NUMBER 11PLSSS
Use the circle below linu
for questions 11.
XV= 24 meters
X
Y
Z
72°
108°
11. Find the length ofw. Round to the nearest hundredth.
Veienwollot
to ribiw

Answers

The length of arc XW is 9,60 metres

The length of arc YVU is 44.93 metres

How to solve

A. M<XZW = 180 degrees - M<VZW

= 180 - 108

= 72 degrees.

XV = 180/360 x 2\pi r =

r = 7.639

XW= 72/360 x 2\pi r

= 9.60 metres.

B. M<UZY = M<XZW = 72 degrees

MYVU= 85 + 180 + 72 = 337 degrees

YVU = 337/360 x 2 pi r

=44.93 metres

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find the value of 3√1 over 16​

Answers

Answer:3/16

Step-by-step explanation:

√1 is the same thing as 1

so (3*1)/16

3/16

josse is collecting signatures for a petition.
He currently has 520signatures.
He has 6 more weeks to collect the signatures he needs.
He needs at least 1000 signatures before he can submit his petition

explain pliss

Answers

The number line that represents all of the possible number of signatures Jesse could collect in each of the remaining weeks so he can have enough signatures to submit the petition is option B.

What is number line?

A number line is a diagram that depicts numbers on a straight line. It is a tool for comparing and sorting numbers. It can represent any real number, including whole numbers and natural numbers.

Jesse currently has 520 signatures and needs at least 1000 signatures, which means he still needs to collect 1000 - 520 = 480 signatures.

He has 6 more weeks to collect the signatures he needs, so he wants to collect the same number of signatures each week. Let's call this number x, representing the number of signatures he collects each week. Then, the total number of signatures he collects in the remaining 6 weeks would be 6x.

We want to find the range of values for x that would allow Jesse to collect at least 480 signatures in the remaining 6 weeks. In other words, we want to solve the inequality:

6x ≥ 480

Dividing both sides by 6, we get:

x ≥ 80

This means that Jesse needs to collect at least 80 signatures per week in order to have enough signatures to submit the petition.

The number line that represents all of the possible number of signatures Jesse could collect in each of the remaining weeks so he can have enough signatures to submit the petition is option B.

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An expression is shown.

12 • 12 • 12 • 12 + 7(3 • 3 • 3 • 3 + 3)

Answers

The last answer should be correct because 12 is listed 4 times and 3 is listed 5 times so it would be 12 with an exponent of 4 + 7 and then 3 with an exponent of 5

suppose that x is a normal random variable with mean 5. if p{x > 9} = .2, approximately what is var(x)?

Answers

suppose that x is a normal random variable with a mean of 5. if p{x > 9} = .2, So, the approximate variance of the normal random variable X is 22.66.

To find the variance of a normal random variable X with mean 5 and given P(X > 9) = 0.2, we will follow these steps:

1. Recognize that X follows a normal distribution: X ~ N(μ, σ²), where μ = 5 and σ² is the variance we want to find.

2. Convert the probability statement P(X > 9) = 0.2 to a standard normal distribution (Z) by finding the corresponding Z-score:
  Z = (X - μ) / σ

3. Look up the Z-score that corresponds to the given probability (0.2) in a standard normal (Z) table. Since the table typically gives P(Z < z), we'll find P(Z < z) = 1 - 0.2 = 0.8. The corresponding Z-score is approximately 0.84.

4. Plug in the known values and solve for σ:
  0.84 = (9 - 5) / σ
  σ ≈ 4 / 0.84
  σ ≈ 4.76

5. Finally, find the variance, which is σ²:
  σ² ≈ 4.76²
  σ² ≈ 22.66

So, the approximate variance of the normal random variable X is 22.66.

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The approximate variance of the normal random variable X is the square of the standard deviation:

Var(X) ≈ [tex](4.76)^2[/tex] ≈ 22.65 (rounded to two decimal places).

To approximate the variance of the normal random variable X with a mean of 5, given that P(X > 9) = 0.2, we can use the z-score and standard normal distribution.

First, we calculate the z-score using the standard normal distribution formula:

z = (X - μ) / σ

where X is the value of interest (in this case, 9), μ is the mean (5), and σ is the standard deviation.

Plugging in the values, we get:

z = (9 - 5) / σ = 4 / σ

Next, we use the standard normal distribution table or a calculator to find the z-score that corresponds to a cumulative probability of 0.2. Let's assume that z = -0.84.

Now, we can use the z-score formula to solve for the standard deviation σ:

-0.84 = 4 / σ

Cross-multiplying, we get:

-0.84σ = 4

Dividing both sides by -0.84, we get:

σ ≈ 4 / -0.84 ≈ -4.76

Since the standard deviation cannot be negative, we discard the negative value and take the absolute value, resulting in:

σ ≈ 4.76

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Liv collected information about the length and width of a random sample of
48
4848 petals of iris flowers. Here are the results:
Width is less than
2
cm
2 cm2, start text, space, c, m, end text Width is more than
2
cm
2 cm2, start text, space, c, m, end text Total
Length is less than
5.2
cm
5.2 cm5, point, 2, start text, space, c, m, end text
14
1414
3
33
17
1717
Length is
5.2
cm
5.2 cm5, point, 2, start text, space, c, m, end text to
5.7
cm
5.7 cm5, point, 7, start text, space, c, m, end text
4
44
11
1111
15
1515
Length is more than
5.7
cm
5.7 cm5, point, 7, start text, space, c, m, end text
7
77
9
9

start box, 9, end box
16
1616
Total
25
2525
23
2323
48
4848
Liv wants to perform a
χ
2
χ
2
\chi, squared test of independence between petal length and width.
What is the expected count for the cell corresponding to petals whose length is more than
5.7
cm
5.7 cm5, point, 7, start text, space, c, m, end text and whose width is more than
2
cm
2 cm2, start text, space, c, m, end text?
You may round your answer to the nearest hundredth.

Answers

The expected count for the cell corresponding to petals whose length is more than 5.7 cm and whose width is more than 2 cm is approximately 7.67.

What is the frequency?

The number of periods or cycles per second is called frequency. The SI unit for frequency is the hertz (Hz). One hertz is the same as one cycle per second.

To find the expected count for the cell corresponding to petals whose length is more than 5.7 cm and whose width is more than 2 cm, we need to calculate the expected frequency for that cell using the formula:

Expected frequency = (row total * column total) / grand total

For this particular cell, the row total is 16 (from the table) and the column total is 23.

The grand total is 48 (also from the table). So, we can calculate the expected frequency as:

Expected frequency = (16 * 23) / 48 = 7.67

Rounding this to the nearest hundredth, we get the expected count as 7.67.

Therefore, the expected count for the cell corresponding to petals whose length is more than 5.7 cm and whose width is more than 2 cm is approximately 7.67.

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Joanna rented a bike for Friday and Saturday. The cost of renting a bike on the weekdays is $7. She used a coupon and paid half the amount on Friday. The amount she paid on Saturday was $4 less than twice the regular cost of renting a bike on weekdays.

How much did she spend on renting the bike?
A.
$13.50
B.
$32.00
C.
$21.50
D.
$24.00

Answers

The solution is A, which is $13.50 as a two-day bike rental normally costs $7 each day multiplied by two days for a total of $14.

what is amount ?

The term "amount" designates a sum or number, typically expressed in terms of monetary value or a tangible good. It can also be used to describe the whole amount of anything, such as the total time that is spent on a work or the total amount of rain that falls in a specific location. "Amount" is frequently used synonymously with "amount" or "total."

given

A two-day bike rental normally costs $7 each day multiplied by two days for a total of $14.

Joanna paid $7/2 ($3.50) on Friday thanks to a voucher she utilised to pay half the price.

The normal Saturday bike rental fee should be "x." Then, according to the issue, Joanna paid $4 less than double what renting a bike normally costs during the workweek. As a result, she spent $10 on Saturday (2($7) - $4).

As a result, she spent the following sum overall to rent the bike:

$3.50 + $10 = $13.50

The solution is A, which is $13.50 as a two-day bike rental normally costs $7 each day multiplied by two days for a total of $14.

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I need help on this I can’t figure it out

Answers

I’m pretty sure the answer is 1,3 since you count up and then turn until you get to the other point

the teacher has a small class with only 7 students. the teacher grades their homework and reports scores of: 10, 7, 8, 12, 9, 11, and 13. what is the median?

Answers

Answer:

10

Step-by-step explanation:

To find the median in a set of data, organize the data from least to greatest.

Here, our data is the homework scores, those being:

10, 7, 8, 12, 9, 11, 13

Let's organize them in ascending order, like so:

7, 8, 9, 10, 11, 12, 13

The next step in finding the median is figuring out which number is in the middle. Since the amount of data we have is an odd number (7), there will be only one number in the middle.

We can find that the number in the middle is 10.

Thus, the median of the scores is 10.

Solve for x please

Choices are...
10
5
25
90

Answers

Answer:

x = 10

Step-by-step explanation:

Angle form is = 90°

therefore

5x + 25 + x + 5 = 90

6x + 30 = 90

6x = 90-30

6x = 60

6x/6 = 60/6

x = 10

Show that cosh2x−sinh2x=1 � � � ℎ 2 � − � � � ℎ 2 � = 1 Differentiate with respect to x � e3xx2+1 � 3 � � 2 + 1 y=secx � = sec ⁡ � y=tanx2 � = tan ⁡ � 2 Differentiate with respect to x � y=ln(x+sinx) � = ln ⁡ ( � + sin ⁡ � ) y=cosxx2 � = cos ⁡ � � 2 Find dydx � � � � given siny+x2y3−cosx=2y sin ⁡ � + � 2 � 3 − cos ⁡ � = 2 � Differentiate from first principles y=cosx � = cos ⁡ � x3+2x2+3x+4 � 3 + 2 � 2 + 3 � + 4 Find d2ydx2 � 2 � � � 2 Given 3x3−6x2+2x−1 3 � 3 − 6 � 2 + 2 � − 1

Answers

We can conclude that cosh2x−sinh2x=1.

What is equation?

An equation is a mathematical statement that states that two expressions are equal. It is typically written as a comparison between two expressions and consists of an equal sign (=). Equations are used to solve mathematical problems, to understand the relationships between different quantities, and to describe the behavior of a physical system. In addition, equations are used to calculate various quantities, such as the area of a circle or the speed of an object.

To show that cosh2x−sinh2x=1, we can use the identities for cosh2x and sinh2x. The identity for cosh2x is cosh2x=2cosh2x−1 and the identity for sinh2x is sinh2x=2sinh2x−1.

Substituting these identities into the equation cosh2x−sinh2x=1 yields 2cosh2x−1−2sinh2x−1=1. Simplifying this equation yields cosh2x−sinh2x=1, as required. Thus, we can conclude that cosh2x−sinh2x=1.

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Simplifying this equation yields [tex]\cosh^2x-sinh^2x=1[/tex], as required. Thus, we can conclude that [tex]\cosh^2x-sinh^2x=1[/tex].

What is equation?

An equation is a mathematical statement that states that two expressions are equal. It is typically written as a comparison between two expressions and consists of an equal sign (=). Equations are used to solve mathematical problems, to understand the relationships between different quantities, and to describe the behavior of a physical system. In addition, equations are used to calculate various quantities, such as the area of a circle or the speed of an object.

We will show that [tex]\cosh^2x-sinh^2x=1[/tex].

Let us consider the expression [tex]\cosh^2x-sinh^2x.[/tex]

Then, [tex]\cosh^2x=(e^2x+e^{-2}x)/2[/tex] and [tex]sinh^2x=(e^2x+e^{-2}x)/2[/tex]

Substituting, we get [tex]\cosh^2x -\sinh^2x=(e^2x+e^{-2}x)/2\ -(e^2x+e^{-2}x)/2[/tex]

Simplifying, we have [tex]\cosh^2x -\sinh^2x=e^2x+e^{-2}x-e^2x+e^{-2}x[/tex]

[tex]=2e^{-2}x\\\\=2(e^{-2}x)\\\\=2[/tex]

Hence, [tex]cosh^2x-sinh^2x=1[/tex]

Therefore, we have shown that [tex]cosh^2x-sinh^2x=1[/tex]

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The correct form of question is Show that cosh2x−sinh2x=1 .

electric utility poles in the form of right cylinders are made out of wood that costs $23.89 per cubic foot. calculate the cost of a utility pole with a diameter of 1.5 ft and a height of 30 ft. round your answer to the nearest cent.

Answers

The cost of the utility pole is approximately $1273.99 when rounded to the nearest cent.

To calculate the cost of the utility pole, we need to find its volume first. The formula for the volume of a cylinder is V = πr^2h, where r is the radius of the base of the cylinder and h is its height.

Here, the diameter of the utility pole is given as 1.5 ft. We need to find the radius, which is half of the diameter, so r = 0.75 ft. The height is given as 30 ft.

Using the formula, we get:

V = πr^2h = π(0.75 ft)^2(30 ft) = 53.36 ft^3

Now, we can calculate the cost of the utility pole by multiplying its volume by the cost of wood per cubic foot, which is $23.89 per cubic foot.

Cost = 53.36 ft^3 x $23.89/ft^3 ≈ $1273.99

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