Question

question 1 of 15
suppose ms. carr is interested in the relationship between her students 9th grade math final exam scores and the number of hours they spent studying during the year. she collects information for 15 ninth grade students and uses it to obtain the regression equation, where x is the number of hours spent studying during the year and ŷ is the predicted final exam score.

y = 1.48x + 75.64

the scatter plot displays her results.

what is the predicted ŷ - value when a student spends 13 hours studying? round your answer to one decimal place.

Explanation:

Step1: Identify the regression equation and x-value

The regression equation is $\hat{y} = 1.48x + 75.64$, and the value of $x$ (hours spent studying) is 13.

Step2: Substitute x = 13 into the equation

Substitute $x = 13$ into $\hat{y} = 1.48x + 75.64$:
$\hat{y} = 1.48(13) + 75.64$
First, calculate $1.48 \times 13$: $1.48 \times 13 = 19.24$
Then, add 75.64: $19.24 + 75.64 = 94.88$

Step3: Round to one decimal place

Round 94.88 to one decimal place. The second decimal digit is 8, which is ≥ 5, so we round up the first decimal digit: $94.88 \approx 94.9$

Answer:

94.9