PSLE A stationery shop is having a book sale.
The 1st book is at 15% 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.
Shiyun and Brandon each bought two books at the sale.
- Shiyun's books were priced at $21 and $27. How much less did she pay for the 2nd book than the 1st book?
- Brandon paid a total of $35.55 for his two books. He paid $10.35 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% $27 |
100% $21 |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85% |
60% |
? |
(a)
Selling price of the 1st book
= 85% x 27
=
85100 x 27
= $22.95
Selling price of 2nd book
= 60% x 21
=
60100 x 21
= $12.60
Amount that Shiyun paid less for the 2nd book than the 1st book
= 22.95 - 12.60
= $10.35
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85%
|
60%
|
|
Compare 1st book and 2nd book |
1 u + $10.35 |
1 u |
$35.55 |
(b)
Sale price of the 1st book = 1 u + 10.35
Sale price of the 2nd book = 1 u
Total amount that Brandon paid
= 1 u + 10.35 + 1 u
= 2 u + 10.35
2 u + 10.35 = 35.55
2 u = 35.55 - 10.35
2 u = 25.20
1 u = 25.20 ÷ 2 = 12.60
Sale price of the 1st book
= 1 u + 10.35
= $22.95
85% of the price = $22.95
100% of the price =
22.9585 x 100 = $27
Selling price of the 1st book before discount = $27
Answer(s): (a) $10.35; (b) $27