PSLE A stationery shop is having a book sale.
The 1st book is at 10% 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.
Risa and Peter each bought two books at the sale.
- Risa's books were priced at $3 and $12. How much did she pay for them?
- Peter paid a total of $50.55 for his two books. He paid $7.05 more for the 1st book than the 2nd book. What was the price of the 2nd book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $12 |
100% $3 |
|
Discount |
- 10% |
- 25% |
|
Sale price |
90% |
75% |
? |
(a)
Selling price of the 1st book
= 90% x 12
=
90100 x 12
= $10.80
Selling price of 2nd book
= 75% x 3
=
75100 x 3
= $2.25
Total amount that Risa paid
= 10.80 + 2.25
= $13.05
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 10% |
- 25% |
|
Sale price |
90%
|
75%
|
|
Compare 1st book and 2nd book |
1 u + $7.05 |
1 u |
$50.55 |
(b)
Sale price of the 1st book = 1 u + 7.05
Sale price of the 2nd book = 1 u
Total amount that Peter paid
= 1 u + 7.05 + 1 u
= 2 u + 7.05
2 u + 7.05 = 50.55
2 u = 50.55 - 7.05
2 u = 43.50
1 u = 43.50 ÷ 2 = 21.75
Sale price of the 2nd book = $21.75
75% of the price = $21.75
100% of the price =
21.7575 x 100 = $29
Selling price of the 2nd book before discount = $29
Answer(s): (a) $13.05; (b) $29