PSLE A store is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 15% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Kylie and Ian each bought two books at the sale.
- Kylie's books were priced at $19 and $30. How much less did she pay for the 2nd book than the 1st book?
- Ian paid a total of $38.10 for his two books. He paid $7.50 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% $19 |
|
Discount |
- 5% |
- 15% |
|
Sale price |
95% |
85% |
? |
(a)
Selling price of the 1st book
= 95% x 30
=
95100 x 30
= $28.50
Selling price of 2nd book
= 85% x 19
=
85100 x 19
= $16.15
Amount that Kylie paid less for the 2nd book than the 1st book
= 28.50 - 16.15
= $12.35
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 15% |
|
Sale price |
95%
|
85%
|
|
Compare 1st book and 2nd book |
1 u + $7.50 |
1 u |
$38.10 |
(b)
Sale price of the 1st book = 1 u + 7.50
Sale price of the 2nd book = 1 u
Total amount that Ian paid
= 1 u + 7.50 + 1 u
= 2 u + 7.50
2 u + 7.50 = 38.10
2 u = 38.10 - 7.50
2 u = 30.60
1 u = 30.60 ÷ 2 = 15.30
Sale price of the 1st book
= 1 u + 7.50
= $22.80
95% of the price = $22.80
100% of the price =
22.8095 x 100 = $24
Selling price of the 1st book before discount = $24
Answer(s): (a) $12.35; (b) $24