The data below are the final exam scores of 10 randomly selected statistics students and the number of hours they studied for the exam. What is the best predicted value for y given x = 7? Assume that the variables x and y have a significant correlation.
Hours, x 3 5 2 8 2 4 4 5 6 3
Scores, y 65 80 60 88 66 78 85 90 90 71
Choose one answer.

A. 89
B. 90
C. 91
D. 92

Correct option: (C) 91.

Step-by-step explanation:

To predict the score received by a student if the number of hours studied is 7 can be done using a regression line.

The general form of a regression line is:

Here,

Y = dependent variable

X = independent variable

α = intercept

β = slope

The formula to compute the slope and intercept are:

Consider the table below.

Compute the value of α as follows:

Compute the value of β as follows:

The regression equation is:

For x = 7 compute the value of y as follows:

Thus, the score received by a student who studied 7 hours is 91.

The correct option is (C).

step-by-step explanation:

first, eliminate the parenthesis:

3

x

+

2

−

4

x

second, group like terms:

3

x

−

4

x

+

2

third, combine like terms:

(

3

−

4

)

x

+

2

→

−

1

x

+

2

→

−

x

+

2

a .4y4

hope this !