PSLE A book shop is having a book sale. The 1st book is at 5% 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.
- Joelle's books were priced at $25 and $28. How much less did she pay for the 2nd book than the 1st book?
- Tim paid a total of $51.65 for his two books. He paid $11.05 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% $28 |
100% $25 |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95% |
70% |
? |
(a)
Selling price of the 1st book
= 95% x 28
=
95100 x 28
= $26.60
Selling price of 2nd book
= 70% x 25
=
70100 x 25
= $17.50
Amount that Joelle paid less for the 2nd book than the 1st book
= 26.60 - 17.50
= $9.10
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $11.05 |
1 u |
$51.65 |
(b)
Sale price of the 1st book = 1 u + 11.05
Sale price of the 2nd book = 1 u
Total amount that Tim paid
= 1 u + 11.05 + 1 u
= 2 u + 11.05
2 u + 11.05 = 51.65
2 u = 51.65 - 11.05
2 u = 40.60
1 u = 40.60 ÷ 2 = 20.30
Sale price of the 1st book
= 1 u + 11.05
= $31.35
95% of the price = $31.35
100% of the price =
31.3595 x 100 = $33
Selling price of the 1st book before discount = $33
Answer(s): (a) $9.10; (b) $33