PSLE A shop is having a book sale.
The 1st book is at 20% discount.
The 2nd book is at 30% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Xuan and Warren each bought two books at the sale.
- Xuan's books were priced at $34 and $39. How much more did she pay for the 1st book than the 2nd book?
- Warren paid a total of $29.50 for his two books. He paid $5.70 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% $39 |
100% $34 |
|
Discount |
- 20% |
- 30% |
|
Sale price |
80% |
70% |
? |
(a)
Selling price of the 1st book
= 80% x 39
=
80100 x 39
= $31.20
Selling price of 2nd book
= 70% x 34
=
70100 x 34
= $23.80
Amount that Xuan paid more for the 1st book than the 2nd book
= 31.20 - 23.80
= $7.40
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 20% |
- 30% |
|
Sale price |
80%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $5.70 |
1 u |
$29.50 |
(b)
Sale price of the 1st book = 1 u + 5.70
Sale price of the 2nd book = 1 u
Total amount that Warren paid
= 1 u + 5.70 + 1 u
= 2 u + 5.70
2 u + 5.70 = 29.50
2 u = 29.50 - 5.70
2 u = 23.80
1 u = 23.80 ÷ 2 = 11.90
Sale price of the 1st book
= 1 u + 5.70
= $17.60
80% of the price = $17.60
100% of the price =
17.6080 x 100 = $22
Selling price of the 1st book before discount = $22
Answer(s): (a) $7.40; (b) $22