PSLE A shop is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 25% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Erika and Elijah each bought two books at the sale.
- Erika's books were priced at $22 and $23. How much more did she pay for the 1st book than the 2nd book?
- Elijah paid a total of $54.70 for his two books. He paid $8.20 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% $23 |
100% $22 |
|
Discount |
- 15% |
- 25% |
|
Sale price |
85% |
75% |
? |
(a)
Selling price of the 1st book
= 85% x 23
=
85100 x 23
= $19.55
Selling price of 2nd book
= 75% x 22
=
75100 x 22
= $16.50
Amount that Erika paid more for the 1st book than the 2nd book
= 19.55 - 16.50
= $3.05
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 25% |
|
Sale price |
85%
|
75%
|
|
Compare 1st book and 2nd book |
1 u + $8.20 |
1 u |
$54.70 |
(b)
Sale price of the 1st book = 1 u + 8.20
Sale price of the 2nd book = 1 u
Total amount that Elijah paid
= 1 u + 8.20 + 1 u
= 2 u + 8.20
2 u + 8.20 = 54.70
2 u = 54.70 - 8.20
2 u = 46.50
1 u = 46.50 ÷ 2 = 23.25
Sale price of the 1st book
= 1 u + 8.20
= $31.45
85% of the price = $31.45
100% of the price =
31.4585 x 100 = $37
Selling price of the 1st book before discount = $37
Answer(s): (a) $3.05; (b) $37