Your teacher surveyed the class to determine the number of hours that each student spent on social media. Your teacher created a table and scatterplot graph that displayed the number of hours, x , and the average final grade percentage, y , based on the hours. Using the equation of the trend line of the data, y=–7.2x+98.9 , predict the average final grade percentage, to the nearest whole number, if a student spent 10 hours on social media.(1 point) Responses The average final grade is 7.2 if a student spent 10 hours on social media. The average final grade is 7.2 if a student spent 10 hours on social media. The average final grade is 99% if a student spent 10 hours on social media. The average final grade is 99% if a student spent 10 hours on social media. The average final grade is 92% if a student spent 10 hours on social media. The average final grade is 92% if a student spent 10 hours on social media. The average final grade is 27% if a student spent 10 hours on social media. The average final grade is 27% if a student spent 10 hours on social media.

1 answer

To predict the average final grade percentage when a student spends 10 hours on social media, we can substitute \( x = 10 \) into the equation of the trend line:

\[ y = -7.2x + 98.9 \]

Substituting \( x = 10 \):

\[ y = -7.2(10) + 98.9 \] \[ y = -72 + 98.9 \] \[ y = 26.9 \]

Rounding this to the nearest whole number, we get:

\[ y \approx 27 \]

Therefore, the predicted average final grade percentage, if a student spent 10 hours on social media, is 27%.