The scatterplot above shows the actual and estimated number of customers visiting a new shopping plaza within the first hour of opening. Which of the following statements correctly compares the rates of incresase for the actual and estimated numbers of customers ?

Options

A. The rate of increases for the actual number of customeers is greater than that of the estimated number is grater than that of the estimatted number in every 20-minute interval.
B. The rate of increase for the actual number of customers is less than that of the estimated number in every 20-minute interval.
C. The rate of incrases for the acutal number of customers is greater than that of the estimated number in the interval from 20 to 40 minutes and less in the interval 40 to 60 minutes.
D. The rate of increase for the actual number of customers is less than that of the estimated number in the interval from 20 to 40 minutes and greater in the interval 40 to 60 minutes.

Answer

C

Explanation

For every 20 minute interval, draw a line of best fit through the data for the actual number of costomeers and similarly for the estimated number of costomers. Then compare the slopes of the lines of best fit for actual and estimated for each 20-minutte interval to compare the rates of increase.
In the interval from 0 to 20 minutes, the slope of the line of best fit for the actual number of costomers is slightly greater (steeper) than that of the estimated model. In the interval from 20 to 40 minutes, the slope of the line of best fit fot the actual data is greater than that of the estimated data. In the interval from 40 to 60 minutes, the slope of the line of best fit for the actual data is less than that of the estimated data. Thus, (C ) is correct.