PSLE A bookstore is having a book sale. The 1st book is at 10% discount. The 2nd book is at 20% discount. The price of the 2nd book should be equal or lower than the price of the 1st book.
- Opal's books were priced at $18 and $23. How much did she pay for them?
- Japheth paid a total of $33.30 for his two books. He paid $4.50 more for the 1st book than the 2nd book. What was the price of the 2nd book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $23 |
100% $18 |
|
Discount |
- 10% |
- 20% |
|
Sale price |
90% |
80% |
? |
(a)
Selling price of the 1st book
= 90% x 23
=
90100 x 23
= $20.70
Selling price of 2nd book
= 80% x 18
=
80100 x 18
= $14.40
Total amount that Opal paid
= 20.70 + 14.40
= $35.10
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 10% |
- 20% |
|
Sale price |
90%
|
80%
|
|
Compare 1st book and 2nd book |
1 u + $4.50 |
1 u |
$33.30 |
(b)
Sale price of the 1st book = 1 u + 4.50
Sale price of the 2nd book = 1 u
Total amount that Japheth paid
= 1 u + 4.50 + 1 u
= 2 u + 4.50
2 u + 4.50 = 33.30
2 u = 33.30 - 4.50
2 u = 28.80
1 u = 28.80 ÷ 2 = 14.40
Sale price of the 2nd book = $14.40
80% of the price = $14.40
100% of the price =
14.4080 x 100 = $18
Selling price of the 2nd book before discount = $18
Answer(s): (a) $35.10; (b) $18