Question

CDs R Us sells books on tape and on Cd. Tapes sell for $10 and Cds sell for $15.

Answer 1

Answer:

10 tapes and 6 Cds

Step-by-step explanation:

As tapes sell for $10 and CD sell for $15, let t be the number of tapes bought and c the number of cds, we can write an equation for the expenditure in the form:

10c + 16t = expenditure

We also n=know she spent 220, so:

10c + 16t = 220

As she bought 16 items, the sum of CD and tapes must be equal to 16. So:

c + t = 16

If we take this last equation and subtract t in both sides:

c = 16 - t

We got the number of CD depending on the number of tapes. We can replace this in the first equation to get t:

10 [16 - t] + 16t = 220

160 - 10 t +16t = 220

160 + 6t = 220

If we subtract 160 in both sides

6t = 220 - 160

6t = 60

Dividing both by 6:

t = 60/6 = 10

So, she purchased 10 tapes. As in total she purchased 16 items she must have purchased 6 cds.

Solution: She purchased 10 tapes and 6 CDs