PSLE A book shop is having a book sale.
The 1st book is at 5% 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.
Cathy and Paul each bought two books at the sale.
- Cathy's books were priced at $21 and $24. How much did she pay for them?
- Paul paid a total of $30.70 for his two books. He paid $11.10 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% $24 |
100% $21 |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95% |
70% |
? |
(a)
Selling price of the 1st book
= 95% x 24
=
95100 x 24
= $22.80
Selling price of 2nd book
= 70% x 21
=
70100 x 21
= $14.70
Total amount that Cathy paid
= 22.80 + 14.70
= $37.50
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95%
|
70%
|
|
Compare 1st book and 2nd book |
1 u + $11.10 |
1 u |
$30.70 |
(b)
Sale price of the 1st book = 1 u + 11.10
Sale price of the 2nd book = 1 u
Total amount that Paul paid
= 1 u + 11.10 + 1 u
= 2 u + 11.10
2 u + 11.10 = 30.70
2 u = 30.70 - 11.10
2 u = 19.60
1 u = 19.60 ÷ 2 = 9.80
Sale price of the 2nd book = $9.80
70% of the price = $9.80
100% of the price =
9.8070 x 100 = $14
Selling price of the 2nd book before discount = $14
Answer(s): (a) $37.50; (b) $14