PSLE A book shop 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.
- Jade's books were priced at $11 and $22. How much did she pay for them?
- Tim paid a total of $32.50 for his two books. He paid $5.30 less for the 2nd book than the 1st book. What was the price of the 2nd book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $22 |
100% $11 |
|
Discount |
- 10% |
- 20% |
|
Sale price |
90% |
80% |
? |
(a)
Selling price of the 1st book
= 90% x 22
=
90100 x 22
= $19.80
Selling price of 2nd book
= 80% x 11
=
80100 x 11
= $8.80
Total amount that Jade paid
= 19.80 + 8.80
= $28.60
|
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 + $5.30 |
1 u |
$32.50 |
(b)
Sale price of the 1st book = 1 u + 5.30
Sale price of the 2nd book = 1 u
Total amount that Tim paid
= 1 u + 5.30 + 1 u
= 2 u + 5.30
2 u + 5.30 = 32.50
2 u = 32.50 - 5.30
2 u = 27.20
1 u = 27.20 ÷ 2 = 13.60
Sale price of the 2nd book = $13.60
80% of the price = $13.60
100% of the price =
13.6080 x 100 = $17
Selling price of the 2nd book before discount = $17
Answer(s): (a) $28.60; (b) $17