Answer:
3.75
Step-by-step explanation:
We have that x is the random variable denoting damage and y is the variable denoting intensity:
they tell us that the interval is [0.3], the variance in this case is the same:
var (x) = var * [E (x | y)] + E * [var (x | y)]
from here we have to:
var (x) = var (y) + E (y ^ 2)
we know that var (y) = E (y ^ 2) - E ^ 2 (y), we replace
var (x) = E (y ^ 2) - E ^ 2 (y) + E (y ^ 2)
var (x) = 2 * E (y ^ 2) - E ^ 2 (y)
We have that E (y ^ 2) = integral from 0 to 3, from 1/3 y ^ 2 * dy
we solve and we are left with:
1/9 and ^ 3, from 0 to 3
(1/9) * (3 ^ 3) - (1/9) * (0 ^ 3) = 3
We also know that E (y) = 3/2
replacing we have:
var (x) = 3 * 2 - (3/2) ^ 2
var (x) = 3.75
Therefore the variance is 3.75
Apply the product rules to determine the sign of each expression
Answer:
Step-by-step explanation:
1). [tex](\frac{-4}{9})\times (\frac{7}{4})=(-1)(\frac{4}{9})(\frac{7}{4} )[/tex]
[tex]=-\frac{7}{9}[/tex] [Negative]
2). [tex](-2\frac{3}{4})(-1\frac{1}{5})=(-1)(2\frac{3}{4})(-1)(1\frac{1}{5})[/tex]
[tex]=(-1)^2(2\frac{3}{4})(1\frac{1}{5})[/tex]
[tex]=(2\frac{3}{4})(1\frac{1}{5})[/tex] [Positive]
3). (3)(-3)(-3)(-3)(-3) = 3.(-1).3.(-1).3.(-1).3(-1).(3)
= (-1)⁴(3)⁵
= (3)⁵ [Positive]
4). [tex](-\frac{1}{6})(-2)(-\frac{3}{5})(-9)[/tex] = [tex](-1)(\frac{1}{6})(-1)(2)(-1)(\frac{3}{5})(-1)(9)[/tex]
= [tex](-1)^4(\frac{1}{6})(2)(\frac{3}{5})(9)[/tex]
= [tex](\frac{1}{6})(2)(\frac{3}{5})(9)[/tex] [Positive]
5). [tex](-\frac{4}{7})(-\frac{3}{5})(-9)=(-1)(\frac{4}{7})(-1)(\frac{3}{5})(-1)(9)[/tex]
[tex]=(-1)^3(\frac{4}{7})(\frac{3}{5})(9)[/tex]
[tex]=-(\frac{4}{7})(\frac{3}{5})(9)[/tex] [Negative]
6). [tex](-\frac{10}{7})(\frac{8}{3})=(-1)(\frac{10}{7})(\frac{8}{3})[/tex]
[tex]=-(\frac{10}{7})(\frac{8}{3})[/tex] [Negative]
A rectangular rug has a perimeter of 460 meters. The width of the rug is five meters more than 4 times the length. Find the
length and the width.
Answer:
Length = 45 m
Width = 185 m
Step-by-step explanation:
Given:
Perimeter of rectangular rug = 460 m
width of the rug is five meters more than 4 times the length
To find:
Width and length of rug = ?
Solution:
Let the length = [tex]l[/tex] m
As per given statement,
Width = [tex]4l+5[/tex] m
Formula for perimeter of a rectangle = [tex]2\times (Length +Width)[/tex]
[tex]460=2\times (l+4l+5)\\\Rightarrow 230 = 5l+5\\\Rightarrow l = \dfrac{225}{5} = 45\ m[/tex]
Width = [tex]4l+5[/tex] m
Width = [tex]4\times 45+5 = 185\ m[/tex]
So, the answer is:
Length = 45 m
Width = 185 m
The difference of m2 + n2 and m + n is
help me pls pls pls please
Hey there! :)
Answer:
y = 5/7x + 2.
Step-by-step explanation:
We can use the slope formula to determine the slope of the line of best fit:
[tex]m = \frac{\text{rise}}{\text{run}} = \frac{y_2 - y_1}{x_2 - x_1}[/tex]
Plug in two points on the line:
[tex]m= \frac{7 - 2}{7 - 0}[/tex]
Simplify:
m = 5/7.
The b value, or y-intercept is at (0, 2). Therefore, this equation in slope-intercept form would be:
y = 5/7x + 2.
The correct choice contains the formula y = 5/7x + 2.
Help me pls pls pls pls
Answer:
The valid point is (5/2, 5)
Step-by-step explanation:
In order to check which ones are valid we will apply all of them to the expression.
(5,15):
[tex]\frac{2}{5}x - \frac{1}{5}y \geq 0\\\\\frac{2}{5}5 - \frac{1}{5}15 \geq 0\\\\-1 \geq 0[/tex]
False.
(1/2, 5):
[tex]\frac{2}{5}x - \frac{1}{5}y \geq 0\\\\\frac{2}{5}\frac{1}{2} - \frac{1}{5}5 \geq 0\\\\-\frac{4}{5} \geq 0[/tex]
False.
(5/2, 5):
[tex]\frac{2}{5}x - \frac{1}{5}y \geq 0\\\\\frac{2}{5}\frac{5}{2} - \frac{1}{5}5 \geq 0\\\\0 \geq 0[/tex]
True.
(2,5):
[tex]\frac{2}{5}x - \frac{1}{5}y \geq 0\\\\\frac{2}{5}2 - \frac{1}{5}5 \geq 0\\\\-\frac{1}{5} \geq 0[/tex]
False
(-1,0):
[tex]\frac{2}{5}x - \frac{1}{5}y \geq 0\\\\\frac{2}{5}(-1) - \frac{1}{5}0 \geq 0\\\\-\frac{2}{5} \geq 0[/tex]
False.
g A population consists of twenty bowerbirds, six of which have bowers featuring reflective decor. If three of the bowerbirds are randomly sampled with replacement from this population, what is closest to the expected number of them that have bowers featuring reflective decor?Group of answer choices00.90.953
Answer:
a ) 0.9
Expected number of bower-birds that have bowers featuring reflective decor
μ = 0.9
Step-by-step explanation:
Explanation:-
Given Sample size 'n' = 20
Given data A population consists of twenty bower-birds, six of which have bowers featuring reflective decor.
probability of success
[tex]p = \frac{x}{n} = \frac{6}{20} =0.3[/tex]
Given three of the bower-birds are randomly sampled with replacement from this population.
So we will choose sample size 'n'= 3
Let 'X' be the random variable in binomial distribution
Expected number of bower-birds that have bowers featuring reflective decor
μ = n p
= 3 × 0.3
=0.9
conclusion:-
Expected number of bower-birds that have bowers featuring reflective decor
μ = 0.9
Write 9x + 3y = 15 in slope-intercept form.
Answer:
y=−3x+5
Step-by-step explanation:
The equation 9x + 3y = 15 in slope-intercept form is y = -3x + 5 where the slope is -3 and intercept is 5
What is an Equation of a line?
The equation of a line is expressed as y = mx + b where m is the slope and b is the y-intercept
And y - y₁ = m ( x - x₁ )
y = y-coordinate of second point
y₁ = y-coordinate of point one
m = slope
x = x-coordinate of second point
x₁ = x-coordinate of point one
The slope m = ( y₂ - y₁ ) / ( x₂ - x₁ )
Given data ,
Let the equation of line be 9x + 3y = 15
Now , the equation can be simplified as
9x + 3y = 15
Divide the equation by 3 , we get
3x + y = 5
Now , the equation of line is of the form y = mx + c , where m is the slope and c is the y intercept
So ,
Subtracting 3x on both sides , we get
y = -3x + 5
So , the equation of line is y = -3x + 5
Hence , The equation 9x + 3y = 15 in slope-intercept form is y = -3x + 5 where the slope is -3 and intercept is 5
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Both the P-value method and the critical value method use the same standard deviation based on the claimed proportion p, so they are equivalent to each other. Is this also true about the confidence interval method?
Answer:
Yes, it's also true about the confidence interval method.
Step-by-step explanation:
The confidence interval includes all the null hypothesis values for the population mean that would be accepted by the hypothesis test at the significance level of 5%. Now, it means this assumes a two-sided alternative.
Now, when testing claims about
population proportions, the critical method and the P-value method are equivalent due to the fact that they always produce the same result. Similarly, a conclusion based on a confidence interval estimate will be the same as a conclusion based on a hypothesis test.
So, Yes the confidence interval method and the P-value or critical methods will always lead to the same conclusion when the tested parameter is the standard deviation.
Brent counted 10 red cards, 10 black cards, and 20 blue cards in a deck of cards. What is the ratio of red cards to other cards? Answers: A) 1:1 B) 1:2 C) 2:1 D) 1:3
Answer:
1:3
Step-by-step explanation:
10 red cards, 10 black cards, and 20 blue cards
We want the ratio of red to other cards
red : blue and black
10 : 10+20
10 : 30
Divide each side by 10
10/10 : 30/10
1:3
Find the lengths of the remaining sides of the triangle. a = 18 a is 60 degrees b is 30 degrees b = c =
Answer:
b= 10.39
c = 20.79
Step-by-step explanation:
a = 60 °
b = 30°
c= 180-(60+30)
c = 180-(90)
c = 90°
Length facing angle a = 18
Let's look for length facing angle b
b/sinb = a/sin a
b/sin 30 = 18/sin 60
b =( 18 * sin30)/sin 60
b = (18*0.5)/0.8660
b = 9/0.8660
b= 10.39
Let's look for c
c/sin c = a/sin a
c/sin 90 = 18/sin 60
c = (18 * sin 90)/sin 60
c =18/0.8660
c = 20.79
Y=-0.71x^4+2.8x^3+27.4 describes the billions of flu virus particles in a persons body x days after being infected.Find the number of virus particles, in billions, after 4 days
Answer:
24.84 billion
Step-by-step explanation:
Put 4 where x is in the equation and do the arithmetic. It can be easier if a little factoring is done first.
y = (-0.71x +2.8)(x^3) +27.4
y = (-0.71(4) +2.8)(64) +27.4
y = 24.84
The formula predicts about 24.84 billion virus particles after 4 days.
To be considered a full-time student at BYU-Idaho, a student must take at least 12 credits in a semester. The maximum number of credits a full-time student can take in a single semester is 21 credits. Assuming Laxman is not taking any part-credit classes, how many different possibilities exist for the number of credits Laxman can take to be considered a full-time student
Answer:
The different possibilities that exist for the number of credits Laxman can take to be considered a full-time student at BYU-Idaho are 10.
Step-by-step explanation:
The least credit a student can take in a semester is 12 credits. The maximum allowed credits in a single semester is 21.
Therefore, Laxman can choose to take from 12 to 21 credits.
Laxman can take 12, 13, 14, 15, 16, 17, 18, 19, 20, or 21 credits. This is equal to {(21 - 12) + 1} = 10.
Laxman cannot take 11 credits and he cannot take 22 credits and there are no part-credit classes, so he is limited to 10 options. Depending on the credit load of courses, he can combine them to achieve or not exceed 21 credits and they must not be below 12 credits.
The number of different possibilities that exist for the number of credits Laxman can take to be considered a full-time student is; 10 different possibilities.
We are told;
Minimum number of credits a full time student can take = 12 credits
Maximum number of credits a full time student can take = 21 credits
This means a full time student can take total credits from 12 credits to 21 credits.
Thus, possible credits a student can take are;
12, 13, 14, 15, 16, 17, 18, 19, 20, 21 credits.
This is a total of 10 possibilities of number of credits a full time student can take.
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add the following - 4/9,7/12and - 3/8
Answer:
[tex] - \frac{17}{72} [/tex]Step-by-step explanation:
[tex] - \frac{4}{9} + \frac{7}{12} + ( - \frac{ 3}{8} )[/tex]
When there is a (+) in front of an expression in parentheses, the expression remains the same:
[tex] - \frac{4}{9} + \frac{7}{12} - \frac{3}{8} [/tex]
[tex] \frac{ - 4 \times 8 + 7 \times 6 - 3 \times 9}{72} [/tex]
Calculate the sum of difference
[tex] \frac{ - 32 + 42 - 27}{72} [/tex]
[tex] \frac{10 - 27}{72} [/tex]
[tex] - \frac{17}{72} [/tex]
Hope this helps..
Good luck on your assignment...
find domain and range using interval notation
Hey there! :)
Answer:
D: [8, 12].
R: [-10, -6].
Step-by-step explanation:
Notice that the endpoints of the graph are closed circles. This means that square brackets will be used:
The graphed equation is from x = 8 to x = 12. Therefore, the domain of the function is:
D: [8, 12].
The range goes from y = -10 to -6. Therefore:
R: [-10, -6].
Answer:
D: [8 , 12]
R: [-10 , -6]
Step-by-step explanation:
Well for this parabola domain and rage are acttually limited because of the solid dots you see on the graph.
So first things first, what is range? Well range is the amount of y values on a line or anything in a graph.
And what’s domain? Domain is the amount of x values on a line or whatnot.
So let’s do domain first.
On the parabola the first x value is 8 and the last is 12 so we have to write this in interval notation which is [8 , 12].
Now for range the lowest y value is -10 and the highest is -6 so in interval notation it is [-10 , -6].
In the figure below, what is the value of xº?
Answer:
[tex] \boxed{\sf x \degree = 62 \degree} [/tex]
Step-by-step explanation:
An exterior angle of a triangle is equal to the sum of the opposite interior angles.
[tex] \sf \implies x \degree + 38 \degree = 100 \degree \\ \\ \sf \implies x \degree + (38 \degree - 38 \degree) = 100 \degree - 38 \degree \\ \\ \sf \implies x \degree = 100 \degree - 38 \degree \\ \\ \sf \implies x \degree = 62 \degree[/tex]
In the given figure, the value of x is 62°.
What is angle ?An angle is the formed when two straight lines meet at one point, it is denoted by θ.
The given angles are,
x°, 38° and 100°.
To find the value of angle x, use exterior angle property.
According to exterior angle property,
The sum of two interior angles is equal to exterior angle.
Since, 100° is the exterior angle of x and 38.
x + 38 = 100
x = 100 - 38
x = 62.
The required value of angle x is 62°.
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Not sure how I would solve this
The first ordered pair is ( -4 , -3 )
The second ordered pair is ( 8, 3 )
=================================================
Explanation:
The first point is (x,-3) where x is unknown. It pairs up with y = -3 so we can use algebra to find x
x-2y = 2
x-2(-3) = 2 ... replace every y with -3; isolate x
x+6 = 2
x = 2-6
x = -4
The first point is (-4, -3)
---------------------------
We'll do something similar for the other point. This time we know x but don't know y. Plug x = 8 into the equation and solve for y
x-2y = 2
8-2y = 2
-2y = 2-8
-2y = -6
y = -6/(-2)
y = 3
The second point is (8, 3)
EACH PAIR OF FIGURES IS SIMILAR. FIND THE MISSING SIDE!!!!
Answer:
58.1 and 17
Step-by-step explanation:
For the first triangles the similarity ratio is 1:7 so x is 8.3 × 7 = 58.1
For the second triangles the similarity ratio is 1:5 so x is 3.4 × 5 = 17
Use cylindrical coordinates. Find the volume of the solid that lies within both the cylinder x2 y2
Answer:
hello your question is incomplete here is the complete question
Use cylindrical coordinates Find the volume of the solid that lies within both the cylinder x^2 + y^2=16 and the sphere x^2 + y^2 + Z^2= 81
Answer : [tex]\frac{4 \pi }{3} [729 - 65\sqrt{65} ][/tex]
Step-by-step explanation:
The given data
cylinder = x^2 + y^2 = 16
sphere = x^2 + y^2 +z^2 = 81
from the given data the solid is symmetric around the xy plane hence we will calculate half the solid volume above the plane then multiply the sesult by 2
Note : we are restricting our attention to the cylinder x^2 + y^2 = 16 and also finding the volume inside the sphere which gives bound on the z-coordinate as well
the r parameter goes from 0 to 4
ATTACHED IS THE REMAINING PART OF THE SOLUTION
showing the integration
A square matrix is called a permutation matrix if it contains the entry 1 exactly once in each row and in each column, with all other entries being 0. All permutation matrices are invertible. Find the inverse of the following permutation matrix.
A = [0 0 1 0, 0 0 0 1, 0 1 0 0, 1 0 0 0]
The inverse of the given permutation matrix A is
[tex]\[ A^{-1} = \begin{bmatrix}0 & 0 & 0 & 1 \\0 & 0 & 1 & 0 \\1 & 0 & 0 & 0 \\0 & 1 & 0 & 0 \\\end{bmatrix} \][/tex]
To find the inverse of the given permutation matrix A:
[tex]\[ A = \begin{bmatrix}0 & 0 & 1 & 0 \\0 & 0 & 0 & 1 \\0 & 1 & 0 & 0 \\1 & 0 & 0 & 0 \\\end{bmatrix} \][/tex]
Utilize the concept that the inverse of a permutation matrix is its transpose.
Therefore, the inverse of matrix A is:
[tex]\[ A^{-1} = A^T \][/tex]
Taking the transpose of matrix A, gives
[tex]\[ A^{-1} = \begin{bmatrix}0 & 0 & 0 & 1 \\0 & 0 & 1 & 0 \\1 & 0 & 0 & 0 \\0 & 1 & 0 & 0 \\\end{bmatrix} \][/tex]
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Identify the vertex of the function. PLEASE HELP!!!
Answer:
Step-by-step explanation:
y-|x|+3
y=|x|+3
vertex=(0,3)
y=|x-4|-7
vertex(4,-7)
Question 1 (1 point)
A CODE has 4 digits. you remember that the 4 digits are 1, 3, 5, and 7, but you
cannot remember the sequence. What is the probability that you guess the code
correctly on the first try?
Answer:
24 ways
Step-by-step explanation:
There are 4!=24 ways to make distinct codes with the given distinct digits. So the probability of guessing it the first time is 1/24.
The probability that you guess the code correctly on the first try will be 1/24.
What is the probability?Probability is synonymous with possibility. It is concerned with the occurrence of a random event.
Probability can only have a value between 0 and 1. Its simple notion is that something is very likely to occur. It is the proportion of favorable events to the total number of events.
If the code is arranged then the total number of ways possible is;
⇒4!
⇒4×3×2×1
⇒24
Possible outcome = 1
Total outcome = 24
Probability = Possible outcome/total outcome
Probability = 1/24
Hence the probability that you guess the code correctly on the first try will be 1/24.
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need answer asap helpppp!!!
Answer:
A.
Step-by-step explanation:
Minor arcs are arcs that are less than 180°. If that is the case, then our only option would be A.
Find the velocity. Please help. Thank you!
Answer:
His final velocity is 48.03 m/s
Step-by-step explanation:
Using SI units (m, kg, s)
a = 3.7
x0 = 25
x1 = 300
v0 = 16.5
Apply kinematics formula
v1^2 - v0^2 = 2a(x1-x0)
solve for v1
Final velocity
v1 = sqrt(2a(x1-x0)+v0^2)
= sqrt( 2(3.7)(300-25)+16.5^2) )
= 48.03 m/s
HELP ME NOWWWWWW PLZZZZZZ EXPLAIN UR ANSWER FOR BRAINLIEST
Answer:
The answer's A 1/52
Step-by-step explanation:
That's because there's only one ace of hearts in a deck of 52 cards.
Answer: A) 1/52
Step-by-step explanation:
There is 52 cards in a whole deck, and the probability of getting that ace card is 1/52 because there is only 1 ace card in an entire deck of cards.
Hence, the answer is 1/52
Please help What is the value of this expression when a = 7 and b = -4? |2a| - b/ 3
Answer:
15 1/3
Step-by-step explanation:
a = 7
b = -4
plugging the above value in |2a| - b/ 3
|2a| - b/ 3 = |2*7| - (-4)/ 3
|x| is modulus function so whatever be the value of be it negative or positive, modulus of this x is positive x
=> |14| + 4/ 3 = 14 + 4/3
=> (14*3 + 4)/3 = (42+4)/3 = 46/3 = 15 1/3
|2a| - b/ 3 = 15 1/3 when a = 7 and b = -4
Previous 20 Two groups leave on different flights from the same airport. Group A flies 200 miles due south, then turns 68° toward west and flies 75 miles. Group B flies 75 miles due north, then turns 51° toward east and flies 200 miles. Which group is farther from the airport?
Answer:
Group B is farther from the airport.
Step-by-step explanation:
To find the distance of each group to the airport we can use the law of cosines in the triangle created with the two movements done and the resulting total distance.
Law of cosines:
[tex]c^2 = a^2 + b^2 - 2ab*cos(angle)[/tex]
For group A, we have the sides of 200 miles and 75 miles, and the angle between the sides is (180-68) = 112°, so the third side of the triangle is:
[tex]c^2 = 200^2 + 75^2 -2*200*75*cos(112)[/tex]
[tex]c^2 = 56863.198[/tex]
[tex]c = 238.46\ miles[/tex]
For group B, we also have the sides of 200 miles and 75 miles, and the angle between the sides is (180-51) = 129°, so the third side of the triangle is:
[tex]c^2 = 200^2 + 75^2 -2*200*75*cos(129)[/tex]
[tex]c^2 = 64504.612[/tex]
[tex]c = 253.98\ miles[/tex]
The distance from group B to the airport is bigger, so group B is farther from the airport.
Consider the matrices. A=⎡⎣⎢4−3−578−2⎤⎦⎥ and B=⎡⎣⎢−27−35−12⎤⎦⎥ What is the result of A−B? Enter your answer by filling in the boxes.
Answer:
Step-by-step explanation:
hello
[tex]A-B=\left[\begin{array}{cc}4-(-2)&7-5\\-3-7&8-(-1)\\-5-(-3)&-2-2\end{array}\right] \\\\=\left[\begin{array}{cc}4+2&2\\-10&8+1\\-5+3&-4\end{array}\right] \\\\=\left[\begin{array}{cc}6&2\\-10&9\\-2&-4\end{array}\right][/tex]
hope this helps
If two matrices are given as,
[tex]X=\begin{bmatrix}a & b\\ c & d\end{bmatrix}[/tex] and [tex]Y=\begin{bmatrix}h & k\\ l & m\end{bmatrix}[/tex]
Then [tex]X-Y=\begin{bmatrix}a-h & b-k\\ c-l & d-m\end{bmatrix}[/tex]
Following this rule answer will be → [tex]A-B=\begin{bmatrix}6 & 2\\ -10 & 9\\ -2 & -4\end{bmatrix}[/tex].
It's given in the question,
Two matrices, [tex]A=\begin{bmatrix}4 & 7\\ -3 & 8\\ -5 & -2\end{bmatrix}[/tex] and [tex]B=\begin{bmatrix}-2 & 5\\ 7 & -1\\ -3 & 2\end{bmatrix}[/tex]
Therefore, [tex]A-B=\begin{bmatrix}4+2 & 7-5\\ -3-7 & 8+1\\ -5+3 & -2-2\end{bmatrix}[/tex]
[tex]A-B=\begin{bmatrix}6 & 2\\ -10 & 9\\ -2 & -4\end{bmatrix}[/tex]
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The surface area of a cube may be found using the formula A=6s^2. What is the edge length of a cube with a surface area of 81 cm^2? Round your answer to the nearest tenth.
Answer: s = 3.7 (rounded 3.67 to the nearest tenth)
Step-by-step explanation:
Surface Area = 81 cm^2
Surface Area of the cube = 6s^2
A = 6s^2
81 = 6s^2
S^2 = 81/6
S = 3.67
Solve: 4^3x=4^2
I need help
Answer: 2/3
Step-by-step explanation:
As the base of the two sides are equal, we can say that
3x = 2 which gives
x = 2/3
Answer:
2/3
Step-by-step explanation:
4^3x=4^2
The bases are the same so the exponents are the same
3x =2
Divide by 3
3x/3 = 2/3
x = 2/3
Sue has $1.80 in dimes and nickels. If she has 9 more dimes than nickels, How many of dimes and nickels does she have?
Answer:
15 dimes6 nickelsStep-by-step explanation:
Let d represent the number of dimes. Then d-9 is the number of nickels. The total value (in cents) is ...
10d +5(d-9) = 180
15d -45 = 180 . . . . . simplify
d -3 = 12 . . . . . . . . . .divide by 15
d = 15
15 -9 = 6 = number of nickels
Sue has 15 dimes and 6 nickels.
Answer:
15 dimes, 6 nickels
Step-by-step explanation:
D = # of dimes, and N = # of nickels
10D + 5N = 180
D = N + 9
Substitute:
10 (N + 9) + 5N = 180
10N + 90 + 5N = 180
15N = 90
N = 6
D = 15