Question

Staples sells cds ($2.00) and boxes of computer paper ($3). If total sales were $1,560 and customers bought 5 times as many cds as boxes of computer paper, how many cds were sold?

Answer 1

CDs: c, Boxes of computer paper: p

c = 5p

2c + 3p = 1560 (the total sales of the items equals $1560)

Plug in the variable value:

2(5p) + 3p = 1560

10p + 3p = 1560

13p = 1560

divide by 13:

p = 120

c = 5 * 120

c = 600

Verify:

2 * 600 + 3 * 120 = 1560

1200 + 360 = 1560

1560 = 1560

Answer: 600 CDs were sold