PSLE A bookstore is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 40% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Irene and Wesley each bought two books at the sale.
- Irene's books were priced at $16 and $18. How much less did she pay for the 2nd book than the 1st book?
- Wesley paid a total of $35.20 for his two books. He paid $12.40 less for the 2nd book than for the 1st book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $18 |
100% $16 |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85% |
60% |
? |
(a)
Selling price of the 1st book
= 85% x 18
=
85100 x 18
= $15.30
Selling price of 2nd book
= 60% x 16
=
60100 x 16
= $9.60
Amount that Irene paid less for the 2nd book than the 1st book
= 15.30 - 9.60
= $5.70
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85%
|
60%
|
|
Compare 1st book and 2nd book |
1 u + $12.40 |
1 u |
$35.20 |
(b)
Sale price of the 1st book = 1 u + 12.40
Sale price of the 2nd book = 1 u
Total amount that Wesley paid
= 1 u + 12.40 + 1 u
= 2 u + 12.40
2 u + 12.40 = 35.20
2 u = 35.20 - 12.40
2 u = 22.80
1 u = 22.80 ÷ 2 = 11.40
Sale price of the 1st book
= 1 u + 12.40
= $23.80
85% of the price = $23.80
100% of the price =
23.8085 x 100 = $28
Selling price of the 1st book before discount = $28
Answer(s): (a) $5.70; (b) $28