Question
Kylie compared attendance rates and grade averages for 10 students using a scatterplot. She fit the data to a line with the equation y = 0.72x + 28.4, where x is the attendance rate as a percent and y is the grade average as a percent.
Find the expected grade of a student with an attendance rate of 80%
Find the expected grade of a student with an attendance rate of 80%
Answers
GPT-4o mini
To find the expected grade of a student with an attendance rate of 80%, we can substitute \( x = 80 \) into the equation of the line:
\[
y = 0.72x + 28.4
\]
Substituting \( x = 80 \):
\[
y = 0.72(80) + 28.4
\]
Calculating \( 0.72 \times 80 \):
\[
0.72 \times 80 = 57.6
\]
Now adding 28.4:
\[
y = 57.6 + 28.4 = 86
\]
Therefore, the expected grade of a student with an attendance rate of 80% is **86%**.
\[
y = 0.72x + 28.4
\]
Substituting \( x = 80 \):
\[
y = 0.72(80) + 28.4
\]
Calculating \( 0.72 \times 80 \):
\[
0.72 \times 80 = 57.6
\]
Now adding 28.4:
\[
y = 57.6 + 28.4 = 86
\]
Therefore, the expected grade of a student with an attendance rate of 80% is **86%**.