PSLE A store 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.
Cindy and Elijah each bought two books at the sale.
- Cindy's books were priced at $24 and $39. How much more did she pay for the 1st book than the 2nd book?
- Elijah paid a total of $41.70 for his two books. He paid $9.50 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% $39 |
100% $24 |
|
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 24
=
70100 x 24
= $16.80
Amount that Cindy paid more for the 1st book than the 2nd book
= 31.20 - 16.80
= $14.40
|
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 + $9.50 |
1 u |
$41.70 |
(b)
Sale price of the 1st book = 1 u + 9.50
Sale price of the 2nd book = 1 u
Total amount that Elijah paid
= 1 u + 9.50 + 1 u
= 2 u + 9.50
2 u + 9.50 = 41.70
2 u = 41.70 - 9.50
2 u = 32.20
1 u = 32.20 ÷ 2 = 16.10
Sale price of the 1st book
= 1 u + 9.50
= $25.60
80% of the price = $25.60
100% of the price =
25.6080 x 100 = $32
Selling price of the 1st book before discount = $32
Answer(s): (a) $14.40; (b) $32