PSLE A stationery shop is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 35% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Gabby and David each bought two books at the sale.
- Gabby's books were priced at $9 and $18. How much did she pay for them?
- David paid a total of $47.50 for his two books. He paid $13.70 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% $18 |
100% $9 |
|
Discount |
- 15% |
- 35% |
|
Sale price |
85% |
65% |
? |
(a)
Selling price of the 1st book
= 85% x 18
=
85100 x 18
= $15.30
Selling price of 2nd book
= 65% x 9
=
65100 x 9
= $5.85
Total amount that Gabby paid
= 15.30 + 5.85
= $21.15
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 35% |
|
Sale price |
85%
|
65%
|
|
Compare 1st book and 2nd book |
1 u + $13.70 |
1 u |
$47.50 |
(b)
Sale price of the 1st book = 1 u + 13.70
Sale price of the 2nd book = 1 u
Total amount that David paid
= 1 u + 13.70 + 1 u
= 2 u + 13.70
2 u + 13.70 = 47.50
2 u = 47.50 - 13.70
2 u = 33.80
1 u = 33.80 ÷ 2 = 16.90
Sale price of the 2nd book = $16.90
65% of the price = $16.90
100% of the price =
16.9065 x 100 = $26
Selling price of the 2nd book before discount = $26
Answer(s): (a) $21.15; (b) $26