PSLE A bookstore 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.
Eva and Mark each bought two books at the sale.
- Eva's books were priced at $17 and $23. How much more did she pay for the 1st book than the 2nd book?
- Mark paid a total of $37.10 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% $23 |
100% $17 |
|
Discount |
- 15% |
- 30% |
|
Sale price |
85% |
70% |
? |
(a)
Selling price of the 1st book
= 85% x 23
=
85100 x 23
= $19.55
Selling price of 2nd book
= 70% x 17
=
70100 x 17
= $11.90
Amount that Eva paid more for the 1st book than the 2nd book
= 19.55 - 11.90
= $7.65
|
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 + $10.50 |
1 u |
$37.10 |
(b)
Sale price of the 1st book = 1 u + 10.50
Sale price of the 2nd book = 1 u
Total amount that Mark paid
= 1 u + 10.50 + 1 u
= 2 u + 10.50
2 u + 10.50 = 37.10
2 u = 37.10 - 10.50
2 u = 26.60
1 u = 26.60 ÷ 2 = 13.30
Sale price of the 1st book
= 1 u + 10.50
= $23.80
85% of the price = $23.80
100% of the price =
23.8085 x 100 = $28
Selling price of the 1st book before discount = $28
Answer(s): (a) $7.65; (b) $28