PSLE A stationery 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.
Penelope and Bobby each bought two books at the sale.
- Penelope's books were priced at $7 and $21. How much did she pay for them?
- Bobby paid a total of $53.85 for his two books. He paid $9.05 more for the 1st book than the 2nd book. What was the price of the 2nd book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $21 |
100% $7 |
|
Discount |
- 15% |
- 30% |
|
Sale price |
85% |
70% |
? |
(a)
Selling price of the 1st book
= 85% x 21
=
85100 x 21
= $17.85
Selling price of 2nd book
= 70% x 7
=
70100 x 7
= $4.90
Total amount that Penelope paid
= 17.85 + 4.90
= $22.75
|
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 + $9.05 |
1 u |
$53.85 |
(b)
Sale price of the 1st book = 1 u + 9.05
Sale price of the 2nd book = 1 u
Total amount that Bobby paid
= 1 u + 9.05 + 1 u
= 2 u + 9.05
2 u + 9.05 = 53.85
2 u = 53.85 - 9.05
2 u = 44.80
1 u = 44.80 ÷ 2 = 22.40
Sale price of the 2nd book = $22.40
70% of the price = $22.40
100% of the price =
22.4070 x 100 = $32
Selling price of the 2nd book before discount = $32
Answer(s): (a) $22.75; (b) $32