Warren and Harry went to buy hard drives at a sale. The usual price of 1 hard drive was $900 each.

SALE
Buy 1 hard drive at 15% discount
Buy 2 or more hard drives at 25% discount each

1. Warren bought 1 hard drive. How much did he pay?
2. What is the maximum number of hard drives Harry can buy if he has $6000?

(a)
Discounted price of 1 hard drive in percent if only 1 was bought
= 100% - 15%
= 85%

100% of 1 hard drive = 900
1% of 1 hard drive = 900 ÷ 100 = 9
85% of 1 hard drive = 85 x 9 = 765 

Amount that Warren paid for 1 hard drive = $765

(b)
Discounted price of 1 hard drive in percent if more than 1 was bought
= 100% - 25%
= 75%

75% of 1 hard drive = 75 x 9 = 675

Amount that Harry paid for 1 hard drive = $675

Maximum number of hard drives that Harry can buy if he has $6000
= 6000 ÷ 675
= 8 r 600

Answer(s): (a) $765; (b) 8