PSLE A bookstore is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 10% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Cathy and Liam each bought two books at the sale.
- Cathy's books were priced at $24 and $30. How much less did she pay for the 2nd book than the 1st book?
- Liam paid a total of $59.45 for his two books. He paid $10.85 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% $24 |
|
Discount |
- 5% |
- 10% |
|
Sale price |
95% |
90% |
? |
(a)
Selling price of the 1st book
= 95% x 30
=
95100 x 30
= $28.50
Selling price of 2nd book
= 90% x 24
=
90100 x 24
= $21.60
Amount that Cathy paid less for the 2nd book than the 1st book
= 28.50 - 21.60
= $6.90
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 10% |
|
Sale price |
95%
|
90%
|
|
Compare 1st book and 2nd book |
1 u + $10.85 |
1 u |
$59.45 |
(b)
Sale price of the 1st book = 1 u + 10.85
Sale price of the 2nd book = 1 u
Total amount that Liam paid
= 1 u + 10.85 + 1 u
= 2 u + 10.85
2 u + 10.85 = 59.45
2 u = 59.45 - 10.85
2 u = 48.60
1 u = 48.60 ÷ 2 = 24.30
Sale price of the 1st book
= 1 u + 10.85
= $35.15
95% of the price = $35.15
100% of the price =
35.1595 x 100 = $37
Selling price of the 1st book before discount = $37
Answer(s): (a) $6.90; (b) $37