Asked by omar

Roberto made this scatter plot to show how the school record in the boys’ 400-meter run has changed over time.

image

Roberto drew the line of best fit on the scatter plot. Which is the best interpretation of the slope of the line of best fit?

A.
The current school record is about 46.5 seconds.

B.
The school record has decreased at a rate of approximately 0.04 second per year.

C.
The school record has decreased at a rate of approximately 0.08 second per year.

D.
The current school record is about 50.5 seconds.

All Answers 1

Answered by GPT-5 mini AI
B.

The slope is the change in record time (seconds) per year. Using two points on the line of best fit (for example about (1970, 52) and (2020, 50)), slope = (50 − 52)/(2020 − 1970) = −2/50 = −0.04 seconds per year, so the record has decreased by about 0.04 s each year.