PSLE A shop is having a book sale.
The 1st book is at 15% 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.
Gabby and Ryan each bought two books at the sale.
- Gabby's books were priced at $9 and $11. How much less did she pay for the 2nd book than the 1st book?
- Ryan paid a total of $46.10 for his two books. He paid $8.30 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% $11 |
100% $9 |
|
Discount |
- 15% |
- 30% |
|
Sale price |
85% |
70% |
? |
(a)
Selling price of the 1st book
= 85% x 11
=
85100 x 11
= $9.35
Selling price of 2nd book
= 70% x 9
=
70100 x 9
= $6.30
Amount that Gabby paid less for the 2nd book than the 1st book
= 9.35 - 6.30
= $3.05
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 30% |
|
Sale price |
85%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $8.30 |
1 u |
$46.10 |
(b)
Sale price of the 1st book = 1 u + 8.30
Sale price of the 2nd book = 1 u
Total amount that Ryan paid
= 1 u + 8.30 + 1 u
= 2 u + 8.30
2 u + 8.30 = 46.10
2 u = 46.10 - 8.30
2 u = 37.80
1 u = 37.80 ÷ 2 = 18.90
Sale price of the 1st book
= 1 u + 8.30
= $27.20
85% of the price = $27.20
100% of the price =
27.2085 x 100 = $32
Selling price of the 1st book before discount = $32
Answer(s): (a) $3.05; (b) $32