PSLE A store is having a book sale.
The 1st book is at 25% 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.
Risa and Liam each bought two books at the sale.
- Risa's books were priced at $14 and $21. How much did she pay for them?
- Liam paid a total of $45.45 for his two books. He paid $7.05 less for the 2nd book than the 1st book. What was the price of the 2nd book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $21 |
100% $14 |
|
Discount |
- 25% |
- 40% |
|
Sale price |
75% |
60% |
? |
(a)
Selling price of the 1st book
= 75% x 21
=
75100 x 21
= $15.75
Selling price of 2nd book
= 60% x 14
=
60100 x 14
= $8.40
Total amount that Risa paid
= 15.75 + 8.40
= $24.15
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 25% |
- 40% |
|
Sale price |
75%
|
60%
|
|
Compare 1st book and 2nd book |
1 u + $7.05 |
1 u |
$45.45 |
(b)
Sale price of the 1st book = 1 u + 7.05
Sale price of the 2nd book = 1 u
Total amount that Liam paid
= 1 u + 7.05 + 1 u
= 2 u + 7.05
2 u + 7.05 = 45.45
2 u = 45.45 - 7.05
2 u = 38.40
1 u = 38.40 ÷ 2 = 19.20
Sale price of the 2nd book = $19.20
60% of the price = $19.20
100% of the price =
19.2060 x 100 = $32
Selling price of the 2nd book before discount = $32
Answer(s): (a) $24.15; (b) $32