Answer:
Step-by-step explanation:
We have to find the reported happiness of person of family income of $25,000, $35,000 and $45,000
Given that the formula for finding relation between a people happiness and his income is
y = 0.065x - 0.613
a) find the happiness of person of family income os $25,000
we put x = 25 as in the equation above
[tex]y=0.065(25)-0.613\\\\=1.625-0.613\\\\=1.02 \approx 1[/tex]
Hence, person happiness with with family income of $25,000 on a scale of 3 is y = 1
That means they come under catergory "not to happy"
b) Find the happiness of person of family income os $35,000
we put x = 35 as in the equation above
[tex]y=0.065(35)-0.613\\\\=1.667-0.613\\\\=1.667 \approx 1.7[/tex]
Hence, person happiness with with family income of $35,000 on a scale of 3 is y = 1.7
That means they come under catergory "not to happy" and "fairly happy"
c) Find the happiness of person of family income os $45,000
we put x = 45 as in the equation above
[tex]y=0.065(45)-0.613\\\\=2.925-0.613\\\\=2.312 \approx 2.3[/tex]
Hence, person happiness with with family income of $45,000 on a scale of 3 is y = 2.3
That means they come under catergory "fairly happy"
The scale would show the data as follows:
Happiness Scale at Income 25, 35, 45 & 55 thousand :
1.012 (Not too happy), 1.662 (Fairly Happy), 2.315 (Fairly Happy) , 2.965 (Very Happy)
Determine the scaleImportant Information :
Relationship between happiness scale 'y' and income in 1000s 'x' :y = 0.065x − 0.613, for people in income group between [tex]25000 & 55000[/tex]
Happiness scale : At level of income, between 25 and 55 thousands.
Putting value of income 'x' to find scale of happiness i.e. 'y'
For income 'x' = 25 thousand : [tex]y = 0.065 (25) - 0.613 = 1.625 - 0.613 = 1.012[/tex] For income 'x' = 35 thousand : [tex]y = 0.065 (35) - 0.613 = 2.275 - 0.613 = 1.662[/tex]For income 'x' = 45 thousand : [tex]y = 0.065 (45) - 0.613 = 2.925 - 0.61 = 2.315[/tex] For income 'x' = 55 thousand :[tex]y = 0.065 (55) - 0.613 = 3.575 - 0.61 = 2.965[/tex]
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whatt is the equation of the line that passes through the points (-3,-3) and (3,1)
Answer:
[tex] m=\frac{y_2 -y_1}{x_2 -x_1}[/tex]
And replacing we got:
[tex] m=\frac{1-(-3)}{3-(-3)}= \frac{4}{6}=\frac{2}{3}[/tex]
And we can use one of the points in order to find the intercept like this:
[tex] -3= \frac{2}{3} (-3) +b[/tex]
[tex] b =-3 +2=-1[/tex]
And the equation would be given by:
[tex] y= \frac{2}{3}x -1[/tex]
Step-by-step explanation:
We want an equation given by:
[tex] y=mx+b[/tex]
where m i the slope and b the intercept
We have the following two points given:
[tex] (x_1 = -3, y_1 =-3), (x_2=3, y_2 =1)[/tex]
We can find the slope with this formula:
[tex] m=\frac{y_2 -y_1}{x_2 -x_1}[/tex]
And replacing we got:
[tex] m=\frac{1-(-3)}{3-(-3)}= \frac{4}{6}=\frac{2}{3}[/tex]
And we can use one of the points in order to find the intercept like this:
[tex] -3= \frac{2}{3} (-3) +b[/tex]
[tex] b =-3 +2=-1[/tex]
And the equation would be given by:
[tex] y= \frac{2}{3}x -1[/tex]
Solve for x
A) 36
B) 54
C) 72
D) 84
Ayo help a girl out
Answer:
72°
Step-by-step explanation:
This is called an isosceles triangle. This means that the 2 angles related to the equal sides, are also equal. Hence, the answer is 72°
Answer:
A
Step-by-step explanation:
Since it is isosceles triangle (two equal sides) therefore, there are 2 equal angles too which at the base (72°)
The total angle of triange is 180°
So 180-72-72=36°
Explain how to find the product of 3/7 X 7/9 . Use complete sentences in your answer.
Answer:
1/3 simplifed.
Step-by-step explanation:
To find the product of 3/7*7/9. We can multiply top and bottom. Top: 3*7=21 Bottom: 7*9=63. Our final answer is just the Top/Bottom= 21/63. We can also simplify this into 1/3 which is our final answer.
James notes the angle of elevation of the top of tower to be 30 degree if James is 100meter away horizontally from the base of the tower find the height of the tower?
Answer:
Around 57.74 feet
Step-by-step explanation:
The tower and James form a right triangle, where the other two angles are 30 degrees and 60 degrees. The tangent of an angle is equivalent to the length of the opposite side divided by the length of the adjacent side, which means:
[tex]\tan 30=\dfrac{x}{100} \\\\x=\tan 30 \cdot 100 \approx 57.74[/tex]
Hope this helps!
if p=7,q=5,r=3 find value of p2+q2-r2
Answer: The value is 18.
Step-by-step explanation:
Since we already know what p, q, and r equal, we can use what we know and plug in the numbers:
p=7, q=5, and r=3,
p2=7*2=14
q2=5*2=10
r2=3*2=6
In conclusion, 14+10-6=18
The value of p2+q2-r2 is 18.
Answer:
Just simply change the variables with their values
7 x 2 + 5 x 2 - 3 x 2
14 + 10 - 6
24 - 6 = 18
18 is the answer
Hope this helps
Step-by-step explanation:
Please help. I’ll mark you as brainliest if correct!
These are 2 math problems .
Answer:
-4 503/12 ≈ 41.91667Step-by-step explanation:
To find the average rate of change, find the change in function value, and divide that by the length of the interval.
1. ((g(1) -g(-1))/(1 -(-1)) = ((-4·1³ +4) -(-4(-1)³ +4)/(2) = (-8)/2 = -4
The average rate of change of g(x) on [-1, 1] is -4.
__
2. ((g(3) -g(-2))/(3 -(-2)) = ((6·3³ +3/3²) -(6·(-2)³ +3/(-2)²))/5
= (6·27 +1/3 -6·(-8) -3/4)/5 = (2515/12)/5
= 503/12 = 41 11/12
The average rate of change of g(x) on [-2, 3] is 41 11/12.
Write a quadratic function f whose zeros are −6 and −1.
Answer:
y = (x+6) (x+1) or in quadratic form: y = x² + 7x + 6
Step-by-step explanation:
For many years "working full-time" was 40 hours per week. A business researcher gathers data on the hours that corporate employees work each week. She wants to determine if corporations now require a longer work week. Group of answer choices Testing a claim about a single population proportion. Testing a claim about a single population mean. Testing a claim about two population proportions. Testing a claim about two population means.
Answer:
Correct option is: Testing a claim about two population means.
Step-by-step explanation:
In this provided scenario, a researchers wants to determine if corporations require a longer work week for the employees "working full-time".
It is given that for many years "working full-time" was 40 hours per week.
The researchers researcher gathers data on the hours that corporate employees work each week.
It is quite clear that the researcher wants to determine whether the number of hours worked per week must be increased from 40 hours or not.
A test for the difference between two population means would help the researcher to reach the conclusion.
Thus, the correct option is: Testing a claim about two population means.
How many commuters must be randomly selected to estimate the mean driving time of Chicago commuters? We want 98% confidence that the sample mean is within 4 minutes of the population mean, and the population standard deviation is known to be 12 minutes. 25 35 49 60
Answer:
49
Step-by-step explanation:
Margin of error = critical value × standard error
ME = CV × SE
The critical value at 98% confidence is z = 2.326.
Standard error is SE = σ / √n.
4 = 2.326 × 12 / √n
n = 49
Use the augmented matrix to determine if the linear system is consistent. Is the linear system represented by the augmented matrix consistent? A. Yes, because the rightmost column of the augmented matrix is a pivot column. B. Yes, because the rightmost column of the augmented matrix is not a pivot column. C. No, because the rightmost column of the augmented matrix is a pivot column. D. No, because the rightmost column of the augmented matrix is not a pivot column.
Answer:
The correct option is (A).
Step-by-step explanation:
If the reduced row echelon form of the coefficient matrix of a linear system of equations in four different variables has a pivot, i.e. 1, in each column, then the reduced row echelon form of the coefficient matrix is say A is an identity matrix, here I₄, since there are 4 variables.
[tex]\left[\begin{array}{cccc}1&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{array}\right][/tex]
Then the corresponding augmented matrix [ A|B] , where the matrix is the representation of the linear system is AX = B, must be:
[tex]\left[\begin{array}{ccccc}1&0&0&0&a\\0&1&0&0&b\\0&0&1&0&c\\0&0&0&1&d\end{array}\right][/tex]
Now the given linear system is consistent as the right most column of the augmented matrix is a linear combination of the columns of A as the reduced row echelon form of A has a pivot in each column.
Thus, the correct option is (A).
If x=10 what is (7x -5)
[tex]solution \\ x = 10 \\ now \\ (7x - 5) \\ = (7 \times 10 - 5) \\ = (70 - 5) \\ = 65[/tex]
Hope it helps....
Good luck on your assignment
Answer:
65
Step-by-step explanation:
= 7x-5
Putting x = 10
= 7(10)-5
= 70-5
= 65
From a barrel of colored marbles, you randomly select 1 blue, 2 yellow, 7 red, 6 green, and 2 purple marbles. Find the experimental probability of randomly selecting a marble that is NOT yellow.
A: 8/9
B: 9/10
C: 11/18
D: 7/9
Answer:
8/9
Step-by-step explanation:
1 blue, 2 yellow, 7 red, 6 green, and 2 purple marbles = 18 marbles
The number that are not yellow = total - yellow
P( not yellow) = number that are not yellow / total
= (18-2) / 18
= 16/18
=8/9
Which of the following shows the extraneous solution to the logarithmic equation log Subscript 7 Baseline (3 x cubed + x) minus log Subscript 7 Baseline (x) = 2 x = negative 16 x = negative 4 x = 4 x = 16
Answer:
x = -4Step-by-step explanation:
A graphing calculator shows there is one solution to ...
[tex]\log_7{(3x^2+x)}-\log_7{(x)}=2[/tex]
However, the usual solution method would be to combine the logarithms and take the antilog to get ...
[tex]\log_7{\left(\dfrac{3x^3+x}{x}\right)}=2\\\\\log_7{(3x^2 +1)}=2\\\\3x^2+1=7^2\\\\x^2=\dfrac{49-1}{3}=16\\\\x=\pm 4\qquad\text{take the square root}[/tex]
This gives two solutions. the "solution" x = -4 is extraneous, as it doesn't work in the original equation. "x" must be positive in the log expressions.
Answer:
x = - 4
Step-by-step explanation:
Got it right :)
PEOPLE! THIS IS URGENT! PLEASE HELP ME!!!! If the product 3/2 · 4/3 · 5/4 · 6/5 ·…· a/b =9, what is the sum of a and b?
Answer:
35
Step-by-step explanation:
3/2 · 4/3 · 5/4 · 6/5 ·…· a/b =9
a+b=?
------
all numbers get cancelled apart from the first denominator and the last numerator:
1/2*a= 9
a= 18then
b= a-1= 18-1= 17a+b= 18+17= 35
What is the volume of the rectangular prism?
Answer:
10ft[tex]{3}[/tex]
Step-by-step explanation:
One face has 15 blocks of 1/3 ft. You can clearly see 2 sets of blocks.
15 x 2 = 30
30 ÷ 3 or 30 x 1/3
= 10 ft cubed
A hospital needs 0.100 gg of 133 54Xe 54133Xe for a lung-imaging test. If it takes 10 daysdays to receive the shipment, what is the minimal amount mXemXem_Xe of xenon that the hospital should order? Express your answer numerically in grams
Answer:
The correct answer will be "0.400 gm".
Step-by-step explanation:
The give values are:
Needs of hospital, N = 0.100 gm
Time, t = 10 days
Minimum amount of Xenon, N₀ = ?
As we know,
⇒ [tex]N(t)=N_{0} \ e^{-\lambda t}[/tex]
∴ Decay constant, λ = [tex]\frac{ln2}{t_{1/2}}[/tex]
λ = [tex]\frac{ln2}{5}[/tex]
On putting values, we get
⇒ [tex]0.100=N_{0} \ e^{-\frac{ln2}{5}}\times 10[/tex]
⇒ [tex]0.1=N_{0} \ e^{-2ln2} = N_{0} \ e^{-ln4}[/tex]
⇒ [tex]0.1=N_{0} \ e^{ln\frac{1}{4}}[/tex]
⇒ [tex]0.1=\frac{N_{0}}{4}[/tex]
⇒ [tex]N_{0}=0.1\times 4[/tex]
⇒ [tex]MX_{e}=0.400 \ gm[/tex]
A 10 foot tree create a shadow that is 15 feet long. Find the angle of elevation of the sun
The angle of elevation of the sun when a 10-foot tree creates a shadow that is 15 feet long is 33.69 degrees
To find the angle of elevation of the sun, we can use trigonometry and the concept of similar triangles.
Given that:
The tree's height is 10 feet.
The length of the shadow is 15 feet.
Let's assume that the tree's height is "h" feet.
Length of its shadow is represented by "s" feet
The angle of elevation of the sun is the angle between the ground and the line from the top of the tree to the tip of its shadow.
The angle can be determined using the tangent function.
[tex]tan\theta[/tex] = [tex]\dfrac{h}{s}[/tex]
Now, substitute the given values:
[tex]tan\theta[/tex]= [tex]\dfrac{10}{15}[/tex]
[tex]tan\theta[/tex] = [tex]\dfrac{2}{3}[/tex]
The angle of elevation can be obtained by taking the inverse tangent of 2/3
angle of elevation =[tex]\tan^-1\dfrac{2}{3}[/tex]
angle of elevation ≈ 33.66 degrees
So, the angle of elevation of the sun is approximately 33.69 degrees.
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In a recent​ year, the total scores for a certain standardized test were normally​ distributed, with a mean of 500 and a standard deviation of 10.4. A) Find the probability that a randomly selected medical student who took the test had a total score that was less than 484. The probability that a randomly selected medical student who took the test had a total score that was less than 484 is:_______.B) Find the probability that a randomly selected study participant's response was between 4 and 6 The probability that a randomly selected study participant's response was between 4 and 6 is:_______.C) Find the probability that a randomly selected study participant's response was more than 8. The probability that a randomly selected study participant's response was more than 8 is:________.
Answer:
A) The probability that a randomly selected medical student who took the test had a total score that was less than 484 = 0.06178
B) The probability that a randomly selected study participant's response was between 504 and 516 = 0.29019
C) The probability that a randomly selected study participant's response was more than 528 = 0.00357
D) Option D is correct.
Only the event in (c) is unusual as its probability is less than 0.05.
Step-by-step explanation:
The b and c parts of the question are not complete.
B) Find the probability that a randomly selected study participant's response was between 504 and 516
C) Find the probability that a randomly selected study participant's response was more than 528.
D) Identify any unusual event amongst the three events in A, B and C. Explain the reasoning.
a) None.
b) Events A and B.
C) Event A
D) Event C
Solution
This is a normal distribution problem with
Mean = μ = 500
Standard deviation = σ = 10.4
A) Probability that a randomly selected medical student who took the test had a total score that was less than 484 = P(x < 484)
We first normalize or standardize 484
The standardized score for any value is the value minus the mean then divided by the standard deviation.
z = (x - μ)/σ = (484 - 500)/10.4 = - 1.54
To determine the required probability
P(x < 484) = P(z < -1.54)
We'll use data from the normal distribution table for these probabilities
P(x < 484) = P(z < -1.54) = 0.06178
B) Probability that a randomly selected study participant's response was between 504 and 516 = P(504 ≤ x ≤ 516)
We normalize or standardize 504 and 516
For 504
z = (x - μ)/σ = (504 - 500)/10.4 = 0.38
For 516
z = (x - μ)/σ = (516 - 500)/10.4 = 1.54
To determine the required probability
P(504 ≤ x ≤ 516) = P(0.38 ≤ z ≤ 1.54)
We'll use data from the normal distribution table for these probabilities
P(504 ≤ x ≤ 516) = P(0.38 ≤ z ≤ 1.54)
= P(z ≤ 1.54) - P(z ≤ 0.38)
= 0.93822 - 0.64803
= 0.29019
C) Probability that a randomly selected study participant's response was more than 528 = P(x > 528)
We first normalize or standardize 528
z = (x - μ)/σ = (528 - 500)/10.4 = 2.69
To determine the required probability
P(x > 528) = P(z > 2.69)
We'll use data from the normal distribution table for these probabilities
PP(x > 528) = P(z > 2.69) = 1 - P(z ≤ 2.69)
= 1 - 0.99643
= 0.00357
D) Only the event in (c) is unusual as its probability is less than 0.05.
Hope this Helps!!!
What’s the correct answer for this?
Answer:
B.
Step-by-step explanation:
Using the formula
S = r∅
Where s is Arc length,l
R is radius
∅ is radian measure for angle RAD
Substituting
L = R∅
So
∅ = L/R
you will get alot of points if you answer this explain your answer
Answer:
The surface area of stand is 46 feet.
First
taking the upper rectangular prism only.
so we get
l=3
w=1
h=3
surface area of rectangular prism = 2lw+2lh+2hw
= 2×3×1+2×3×3+2×3×1
= 30
taking the lower rectangular prism only.
surface area of rectangular prism = 2lw+2lh+2hw
=2×7×2+2×1×7+2×2×1
=46
add both the rectangular prism.
we get,
30+46
76
Yes, $15 is enough
Taking out the square of all the rectangle the total would be 52m²
52/25×6.79 ( as 6.79 dollars for 25 m²)
$14.1232
Answer:
freecoins
Step-by-step explanation:
What is the simplified value of the exponential expression 27 1/3 ?
1/3
1/9
3
9
Answer:
3
Step-by-step explanation:
27^1/3 = cuberoot(27) = 3
Carole's age is five times Joe's age. The sum of their ages is 18. How old are Carole and Joe?
Answer:
Carole is 15
Joe is 3
Step-by-step explanation:
Carole's age is 15
Joes age is 3
3*5=15
15+3=18
Answer:
Carole = 15 Yrs
Joe = 3 Yrs
Step-by-step explanation:
15/5 =3
15+3 =18
Sry for the short explanation. Hope this helps!
A flexible cable always hangs in the shape of a catenary curve y = c + a cosh(x/a), where cand a are constants, a > 0. Suppose a telephone line hangs between two poles 18 meters apart, in the shape of the catenary y = 30 cosh(x/15) - 4, where x and y are measured in meters. a. (3 pts.) Find the slope of this curve where it meets the right pole. (Round to 3 decimal places.] b. (3 pts.) Find the angle between the line and the right pole. [Give your answer in degrees, rounded to the nearest hundredth.) Expert Answer
Answer:
The slope of this curve where it meets the right pole is 1.130
The angle between the line and the right pole is 41.51 °
Step-by-step explanation:
Given that ;
[tex]y = 30 \ cos h (\dfrac{x}{15} - 4)[/tex]
[tex]\dfrac{dy}{dx}= \dfrac{30}{15} sinh(\dfrac{x}{15})[/tex]
[tex]\dfrac{dy}{dx}=2 \ sinh(\dfrac{x}{15})[/tex]
x = 9 m;( i.e half of the distance of the two poles at 18 meters apart.
[tex]\dfrac{dy}{dx}=2 \ sinh(\dfrac{9}{15})[/tex]
= 1.130
The slope of this curve where it meets the right pole is 1.130
The angle between the line an the right rope can be determined by using the tangent of the slope .
tan ∝ = 1.130
∝ = tan⁻¹ (1.130)
∝ = 48.49°
The angle is θ; so
θ = 90 - ∝
θ = 90 - 48.49°
θ = 41.51 °
Thus; the angle between the line and the right pole is 41.51 °
Outcome
0
1
5
10
1000
Probability
0.33
0.32
0.24
0.10
0.01
Which is the expected value of the random variable with the given probability distribution?
a.
5.65
c.
12.52
b.
100.44
d.
5
Answer:
The expected value of the random variable with the given probability distribution = 12 .52
Step-by-step explanation:
Given data
x : 0 1 5 10 1000
p(x) : 0.33 0.32 0.24 0.10 0.01
The expected value of the given random variable of given probability distribution
E(X) = ∑ x p ( X = x)
E(X) = 0 × 0.33 + 1 × 0.32 + 5 × 0.24 + 10× 0.10 + 1000×0.01
E (X) = 12.52
What letter completes the puzzle? The answer is probably easy for you guys but I don't understand how the letters go along with the puzzle. Thank you!
Answer:
the answer is E the number at the top tells you which position it falls under in the alphabet
It is known that 50% of adult workers have a high school diploma. If a random sample of 8 adult workers is selected, what is the probability that less than 6 of them have a high school diploma
Answer:
85.56% probability that less than 6 of them have a high school diploma
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they have a high school diploma, or they do not. The probability of an adult having a high school diploma is independent of other adults. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
50% of adult workers have a high school diploma.
This means that [tex]p = 0.5[/tex]
If a random sample of 8 adult workers is selected, what is the probability that less than 6 of them have a high school diploma
This is P(X < 6) when n = 8.
[tex]P(X < 6) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) + P(X = 5)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{8,0}.(0.5)^{0}.(0.5)^{8} = 0.0039[/tex]
[tex]P(X = 1) = C_{8,1}.(0.5)^{1}.(0.5)^{7} = 0.0313[/tex]
[tex]P(X = 2) = C_{8,2}.(0.5)^{2}.(0.5)^{6} = 0.1094[/tex]
[tex]P(X = 3) = C_{8,3}.(0.5)^{3}.(0.5)^{5} = 0.2188[/tex]
[tex]P(X = 4) = C_{8,4}.(0.5)^{4}.(0.5)^{4} = 0.2734[/tex]
[tex]P(X = 5) = C_{8,5}.(0.5)^{5}.(0.5)^{3} = 0.2188[/tex]
[tex]P(X < 6) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) + P(X = 5) = 0.0039 + 0.0313 + 0.1094 + 0.2188 + 0.2734 + 0.2188 = 0.8556[/tex]
85.56% probability that less than 6 of them have a high school diploma
find the area of the triangle. ? square units
Answer:
54 square units
Step-by-step explanation:
The formula for the area of a triangle is:
[tex]\frac{1}{2}[/tex] x base x height
The base is 12
The height is 9
So 1/2 x 12 x 9 = 54 square units
Solve for B. R = x(A + B)
Answer:
B = R/x -A
Step-by-step explanation:
[tex]\text{Divide the equation by x:}\\\\\dfrac{R}{x}=A+B\\\\\text{Subtract A:}\\\\\dfrac{R}{x}-A = B\\\\\text{The solution is ...}\\\\\boxed{B=\dfrac{R}{x}-A}[/tex]
Answer:
[tex] b = \frac{r - ax}{x} \\ [/tex]
Step-by-step explanation:
[tex]r = x(a + b) \\ r = ax + bx \\ r - ax = bx \\ \frac{r - ax}{x} = b[/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
A) Divide 160km in the ratio 10:9:13
B) divide 66 in the ratio 6:15:1
Answer:
A) 50 km : 45 km : 65 km
B) 18:45:3
Step-by-step explanation:
A) 160 km in the ratio 10:9:13
10x+9x+13x= 16032x= 160x= 510:9:3 ⇔ 50 km : 45 km : 65 km
B) 66 in the ratio 6:15:1
6x+15x+x= 6622x=66x=36:15:1 ⇔ 18:45:3
The following data values represent a population. What is the variance of the
values?
8, 10, 14,4
A. 14
B. 10
C. 9
D. 13
Answer:
D: 13
So first you write down your equation ( its on the picture I posted) Then you need to find the mean which is the sum of all the values over the number of values you have (n) After finding your mean, you subtract it from every value you have. To check if what you have done is correct you add all the values you got after subtracting, if you get 0 your answer is correct. Then you square each of those answers you get after you subtract. You get the total which you then divide by the number of values you have (n)
I hope you understand, I am not that good at explaining. And I am not completely sure with my answer, but I think it's correct.