PSLE A stationery shop is having a book sale.
The 1st book is at 10% 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.
Sabrina and Vaidev each bought two books at the sale.
- Sabrina's books were priced at $24 and $39. How much more did she pay for the 1st book than the 2nd book?
- Vaidev paid a total of $27.30 for his two books. He paid $10.50 less for the 2nd book than for the 1st book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $39 |
100% $24 |
|
Discount |
- 10% |
- 30% |
|
Sale price |
90% |
70% |
? |
(a)
Selling price of the 1st book
= 90% x 39
=
90100 x 39
= $35.10
Selling price of 2nd book
= 70% x 24
=
70100 x 24
= $16.80
Amount that Sabrina paid more for the 1st book than the 2nd book
= 35.10 - 16.80
= $18.30
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 10% |
- 30% |
|
Sale price |
90%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $10.50 |
1 u |
$27.30 |
(b)
Sale price of the 1st book = 1 u + 10.50
Sale price of the 2nd book = 1 u
Total amount that Vaidev paid
= 1 u + 10.50 + 1 u
= 2 u + 10.50
2 u + 10.50 = 27.30
2 u = 27.30 - 10.50
2 u = 16.80
1 u = 16.80 ÷ 2 = 8.40
Sale price of the 1st book
= 1 u + 10.50
= $18.90
90% of the price = $18.90
100% of the price =
18.9090 x 100 = $21
Selling price of the 1st book before discount = $21
Answer(s): (a) $18.30; (b) $21