PSLE A stationery shop is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 25% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Winnie and Liam each bought two books at the sale.
- Winnie's books were priced at $10 and $14. How much more did she pay for the 1st book than the 2nd book?
- Liam paid a total of $28.20 for his two books. He paid $11.70 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% $14 |
100% $10 |
|
Discount |
- 5% |
- 25% |
|
Sale price |
95% |
75% |
? |
(a)
Selling price of the 1st book
= 95% x 14
=
95100 x 14
= $13.30
Selling price of 2nd book
= 75% x 10
=
75100 x 10
= $7.50
Amount that Winnie paid more for the 1st book than the 2nd book
= 13.30 - 7.50
= $5.80
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 25% |
|
Sale price |
95%
|
75%
|
|
Compare 1st book and 2nd book |
1 u + $11.70 |
1 u |
$28.20 |
(b)
Sale price of the 1st book = 1 u + 11.70
Sale price of the 2nd book = 1 u
Total amount that Liam paid
= 1 u + 11.70 + 1 u
= 2 u + 11.70
2 u + 11.70 = 28.20
2 u = 28.20 - 11.70
2 u = 16.50
1 u = 16.50 ÷ 2 = 8.25
Sale price of the 1st book
= 1 u + 11.70
= $19.95
95% of the price = $19.95
100% of the price =
19.9595 x 100 = $21
Selling price of the 1st book before discount = $21
Answer(s): (a) $5.80; (b) $21