PSLE A store 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.
Winnie and Paul each bought two books at the sale.
- Winnie's books were priced at $21 and $30. How much more did she pay for the 1st book than the 2nd book?
- Paul paid a total of $50.40 for his two books. He paid $10.80 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% $30 |
100% $21 |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85% |
60% |
? |
(a)
Selling price of the 1st book
= 85% x 30
=
85100 x 30
= $25.50
Selling price of 2nd book
= 60% x 21
=
60100 x 21
= $12.60
Amount that Winnie paid more for the 1st book than the 2nd book
= 25.50 - 12.60
= $12.90
|
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 + $10.80 |
1 u |
$50.40 |
(b)
Sale price of the 1st book = 1 u + 10.80
Sale price of the 2nd book = 1 u
Total amount that Paul paid
= 1 u + 10.80 + 1 u
= 2 u + 10.80
2 u + 10.80 = 50.40
2 u = 50.40 - 10.80
2 u = 39.60
1 u = 39.60 ÷ 2 = 19.80
Sale price of the 1st book
= 1 u + 10.80
= $30.60
85% of the price = $30.60
100% of the price =
30.6085 x 100 = $36
Selling price of the 1st book before discount = $36
Answer(s): (a) $12.90; (b) $36