PSLE A book shop is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 30% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Winnie and Oliver each bought two books at the sale.
- Winnie's books were priced at $28 and $30. How much more did she pay for the 1st book than the 2nd book?
- Oliver paid a total of $41.75 for his two books. He paid $9.55 more for the 1st book than for the 2nd book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $30 |
100% $28 |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95% |
70% |
? |
(a)
Selling price of the 1st book
= 95% x 30
=
95100 x 30
= $28.50
Selling price of 2nd book
= 70% x 28
=
70100 x 28
= $19.60
Amount that Winnie paid more for the 1st book than the 2nd book
= 28.50 - 19.60
= $8.90
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $9.55 |
1 u |
$41.75 |
(b)
Sale price of the 1st book = 1 u + 9.55
Sale price of the 2nd book = 1 u
Total amount that Oliver paid
= 1 u + 9.55 + 1 u
= 2 u + 9.55
2 u + 9.55 = 41.75
2 u = 41.75 - 9.55
2 u = 32.20
1 u = 32.20 ÷ 2 = 16.10
Sale price of the 1st book
= 1 u + 9.55
= $25.65
95% of the price = $25.65
100% of the price =
25.6595 x 100 = $27
Selling price of the 1st book before discount = $27
Answer(s): (a) $8.90; (b) $27