Question

The table shows the amount of money Jackie charges for a box of candy as a function of the number of boxes of candy she has sold.

Candy Boxes
Number of Boxes of Candy, x Amount Charged, y (dollars)
1 12.25
3 25.75
4 32.50
7 52.75
10 73.00


Based on the table, which function models this situation?

A
y = 13.5x − 1.25
B
y = 13.5x + 12.25
C
y = 5.5x + 6.75
D
y = 6.75x + 5.5

Answer 1

First find the rate (slope). Between x=1 and x=3: (25.75−12.25)/(3−1)=13.5/2=6.75.
So y = 6.75x + b. Use (1,12.25): 12.25 = 6.75(1)+b → b = 5.5.
Thus y = 6.75x + 5.5, option D.