A student makes money by watching the neighbors’ dog. The situation is modeled in the graph below.

Question

The graph titled money made shows Fee in dollars from 0 to 130 on the y axis in increments of 10 and time in days from 0 to 10 the line passes through the points (0, 20), (1, 30), (2, 40).

Which statement correctly describes the relationship between the amount of money the student makes and time in days?

A.
The student charges $11 plus an additional $20 per day.

B.
The student charges $20 plus an additional $11 per day.

C.
The student charges $20 plus an additional $10 per day.

D.
The student charges $10 plus an additional $20 per day.

Answer 1

To determine the correct statement about the relationship between the amount of money the student makes and time in days, we can analyze the points given on the graph:

• At 0 days, the student makes $20.
• At 1 day, the student makes $30.
• At 2 days, the student makes $40.

From this information, we see:

• The starting amount (y-intercept) is $20.
• The change in amount per day from 1 day to the next is $10. (30 - 20 = 10 and 40 - 30 = 10)

This pattern indicates that the student charges a base fee of $20 and an additional $10 per day.

Therefore, the correct statement is:

C. The student charges $20 plus an additional $10 per day.