PSLE A bookstore is having a book sale.
The 1st book is at 25% 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.
Kathy and Tim each bought two books at the sale.
- Kathy's books were priced at $24 and $39. How much less did she pay for the 2nd book than the 1st book?
- Tim paid a total of $28.35 for his two books. He paid $3.15 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% $24 |
|
Discount |
- 25% |
- 30% |
|
Sale price |
75% |
70% |
? |
(a)
Selling price of the 1st book
= 75% x 39
=
75100 x 39
= $29.25
Selling price of 2nd book
= 70% x 24
=
70100 x 24
= $16.80
Amount that Kathy paid less for the 2nd book than the 1st book
= 29.25 - 16.80
= $12.45
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 25% |
- 30% |
|
Sale price |
75%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $3.15 |
1 u |
$28.35 |
(b)
Sale price of the 1st book = 1 u + 3.15
Sale price of the 2nd book = 1 u
Total amount that Tim paid
= 1 u + 3.15 + 1 u
= 2 u + 3.15
2 u + 3.15 = 28.35
2 u = 28.35 - 3.15
2 u = 25.20
1 u = 25.20 ÷ 2 = 12.60
Sale price of the 1st book
= 1 u + 3.15
= $15.75
75% of the price = $15.75
100% of the price =
15.7575 x 100 = $21
Selling price of the 1st book before discount = $21
Answer(s): (a) $12.45; (b) $21