PSLE A stationery shop is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 35% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Jade and Justin each bought two books at the sale.
- Jade's books were priced at $25 and $33. How much more did she pay for the 1st book than the 2nd book?
- Justin paid a total of $42.40 for his two books. He paid $8.60 less for the 2nd book than for the 1st book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $33 |
100% $25 |
|
Discount |
- 15% |
- 35% |
|
Sale price |
85% |
65% |
? |
(a)
Selling price of the 1st book
= 85% x 33
=
85100 x 33
= $28.05
Selling price of 2nd book
= 65% x 25
=
65100 x 25
= $16.25
Amount that Jade paid more for the 1st book than the 2nd book
= 28.05 - 16.25
= $11.80
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 35% |
|
Sale price |
85%
|
65%
|
|
Compare 1st book and 2nd book |
1 u + $8.60 |
1 u |
$42.40 |
(b)
Sale price of the 1st book = 1 u + 8.60
Sale price of the 2nd book = 1 u
Total amount that Justin paid
= 1 u + 8.60 + 1 u
= 2 u + 8.60
2 u + 8.60 = 42.40
2 u = 42.40 - 8.60
2 u = 33.80
1 u = 33.80 ÷ 2 = 16.90
Sale price of the 1st book
= 1 u + 8.60
= $25.50
85% of the price = $25.50
100% of the price =
25.5085 x 100 = $30
Selling price of the 1st book before discount = $30
Answer(s): (a) $11.80; (b) $30