PSLE A stationery kiosk is having a book sale.
The 1st book is at 5% 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.
Wendy and Riordan each bought two books at the sale.
- Wendy's books were priced at $2 and $15. How much less did she pay for the 2nd book than the 1st book?
- Riordan paid a total of $50.10 for his two books. He paid $6.90 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% $15 |
100% $2 |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95% |
80% |
? |
(a)
Selling price of the 1st book
= 95% x 15
=
95100 x 15
= $14.25
Selling price of 2nd book
= 80% x 2
=
80100 x 2
= $1.60
Amount that Wendy paid less for the 2nd book than the 1st book
= 14.25 - 1.60
= $12.65
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95%
|
80%
|
|
Compare 1st book and 2nd book |
1 u + $6.90 |
1 u |
$50.10 |
(b)
Sale price of the 1st book = 1 u + 6.90
Sale price of the 2nd book = 1 u
Total amount that Riordan paid
= 1 u + 6.90 + 1 u
= 2 u + 6.90
2 u + 6.90 = 50.10
2 u = 50.10 - 6.90
2 u = 43.20
1 u = 43.20 ÷ 2 = 21.60
Sale price of the 1st book
= 1 u + 6.90
= $28.50
95% of the price = $28.50
100% of the price =
28.5095 x 100 = $30
Selling price of the 1st book before discount = $30
Answer(s): (a) $12.65; (b) $30