PSLE A shop is having a book sale. The 1st book is at 15% 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.
- Marion's books were priced at $31 and $37. How much more did she pay for the 1st book than the 2nd book?
- Liam paid a total of $43.40 for his two books. He paid $5.90 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% $37 |
100% $31 |
|
Discount |
- 15% |
- 25% |
|
Sale price |
85% |
75% |
? |
(a)
Selling price of the 1st book
= 85% x 37
=
85100 x 37
= $31.45
Selling price of 2nd book
= 75% x 31
=
75100 x 31
= $23.25
Amount that Marion paid more for the 1st book than the 2nd book
= 31.45 - 23.25
= $8.20
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 25% |
|
Sale price |
85%
|
75%
|
|
Compare 1st book and 2nd book |
1 u + $5.90 |
1 u |
$43.40 |
(b)
Sale price of the 1st book = 1 u + 5.90
Sale price of the 2nd book = 1 u
Total amount that Liam paid
= 1 u + 5.90 + 1 u
= 2 u + 5.90
2 u + 5.90 = 43.40
2 u = 43.40 - 5.90
2 u = 37.50
1 u = 37.50 ÷ 2 = 18.75
Sale price of the 1st book
= 1 u + 5.90
= $24.65
85% of the price = $24.65
100% of the price =
24.6585 x 100 = $29
Selling price of the 1st book before discount = $29
Answer(s): (a) $8.20; (b) $29