PSLE A bookstore 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.
Min and Ken each bought two books at the sale.
- Min's books were priced at $19 and $31. How much more did she pay for the 1st book than the 2nd book?
- Ken paid a total of $45.30 for his two books. He paid $11.70 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% $31 |
100% $19 |
|
Discount |
- 5% |
- 30% |
|
Sale price |
95% |
70% |
? |
(a)
Selling price of the 1st book
= 95% x 31
=
95100 x 31
= $29.45
Selling price of 2nd book
= 70% x 19
=
70100 x 19
= $13.30
Amount that Min paid more for the 1st book than the 2nd book
= 29.45 - 13.30
= $16.15
|
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 + $11.70 |
1 u |
$45.30 |
(b)
Sale price of the 1st book = 1 u + 11.70
Sale price of the 2nd book = 1 u
Total amount that Ken paid
= 1 u + 11.70 + 1 u
= 2 u + 11.70
2 u + 11.70 = 45.30
2 u = 45.30 - 11.70
2 u = 33.60
1 u = 33.60 ÷ 2 = 16.80
Sale price of the 1st book
= 1 u + 11.70
= $28.50
95% of the price = $28.50
100% of the price =
28.5095 x 100 = $30
Selling price of the 1st book before discount = $30
Answer(s): (a) $16.15; (b) $30