PSLE A shop is having a book sale.
The 1st book is at 20% 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.
Barbara and Tommy each bought two books at the sale.
- Barbara's books were priced at $2 and $12. How much more did she pay for the 1st book than the 2nd book?
- Tommy paid a total of $36.70 for his two books. He paid $8.10 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% $12 |
100% $2 |
|
Discount |
- 20% |
- 35% |
|
Sale price |
80% |
65% |
? |
(a)
Selling price of the 1st book
= 80% x 12
=
80100 x 12
= $9.60
Selling price of 2nd book
= 65% x 2
=
65100 x 2
= $1.30
Amount that Barbara paid more for the 1st book than the 2nd book
= 9.60 - 1.30
= $8.30
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 20% |
- 35% |
|
Sale price |
80%
|
65%
|
|
Compare 1st book and 2nd book |
1 u + $8.10 |
1 u |
$36.70 |
(b)
Sale price of the 1st book = 1 u + 8.10
Sale price of the 2nd book = 1 u
Total amount that Tommy paid
= 1 u + 8.10 + 1 u
= 2 u + 8.10
2 u + 8.10 = 36.70
2 u = 36.70 - 8.10
2 u = 28.60
1 u = 28.60 ÷ 2 = 14.30
Sale price of the 1st book
= 1 u + 8.10
= $22.40
80% of the price = $22.40
100% of the price =
22.4080 x 100 = $28
Selling price of the 1st book before discount = $28
Answer(s): (a) $8.30; (b) $28