Question

Christine went shopping and bought each of her eight nephews a gift, either a video costing $14.95 or a CD costing $16.88. She spent $131.18 on the gifts. How many

videos and how many CDs did she buy?

Answer 1

Explanation:

Define number of videos purchased as "n" and number of CD's purchased as "c" then we can equation the total purchases and the costs by:

8 nephews:

n + c = 8

Spent $121.53

14.95*n + 16.88*c = 121.53

Substitute one variable as a function of the other. Preference the simpler equation (n + c = 8)

n = 8 - c

=>

14.95*(8-c) + 16.88c = 121.53

119.60 + 1.93c = 121.53

1.93c = 1.93

c = 1

=>

n = 7

*Check:

14.95*(7) + 16.88*(1) = 121.53

im so sorry if this is wrong :/