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#### A small car dealership tests the fuel efficiency of sedans on its lot. It chooses 12 sedans for the test. The fuel efficiency (mpg) values of the cars are given in the table below. Complete the table as directed below

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Anonymous
0

a.  Calculate the mean fuel efficiency for these cars.

b.  Calculate the deviations from the mean, and write your answers in the second row of the table.

c. Square the deviations from the mean, and write the squared deviations in the third row of the table.

d. Find the sum of the squared deviations

e. What is the value of n for this data set? Divide the sum of the squared deviations by n - 1

https://www.engageny.org/resource/high-school-algebra-i

Sangeetha Pulapaka
0

Step 1: Recall on how to calculate the mean

https://www.qalaxia.com/viewDiscussion?messageId=5cc92d629a8f715227163212

\frac{29 +35+24+25+21+21+18+28+31+26+26+22}{12} = 25.5

Step 2: Subtract the given mean from the mean got above to get the deviations from the mean

29 - 25.5 = 3.5

35 - 25.5 = 9.5

24 - 25.5 = -1.5

25 - 25.5 = -0.5

21 - 25.5 = -4.5 etc.

Doing this we get the values

Step 3: Recall on how to square values

https://www.qalaxia.com/viewDiscussion?messageId=5cd50b35e40a50263e6e122a

Square the values got above to get

Step 4: Find the sum of the squared deviations

Recall on how to add more than two decimals

https://www.qalaxia.com/viewDiscussion?messageId=5cd5109ae40a50263e6e123f

Add 12.25 +90.25 + 2.25 +0.25 +20.25 +56.25 +6.25 + 30.25 + 0.25 +12.25  to get

251

Step 5: Calculate the mean of this data set

n = 12

\frac{251}{11}= 22.818 to the nearest thousndth.

Which is also the variance, since

[squaring deviation from the mean] ÷ number of observations = variance

https://www.engageny.org/resource/high-school-algebra-i

Aaron Horton
0
WHat THe FRiCk?!