PSLE A stationery shop is having a book sale. The 1st book is at 10% discount. The 2nd book is at 15% discount. The price of the 2nd book should be equal or lower than the price of the 1st book.
- Winnie's books were priced at $35 and $39. How much more did she pay for the 1st book than the 2nd book?
- Ethan paid a total of $43.85 for his two books. He paid $4.75 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% $39 |
100% $35 |
|
Discount |
- 10% |
- 15% |
|
Sale price |
90% |
85% |
? |
(a)
Selling price of the 1st book
= 90% x 39
=
90100 x 39
= $35.10
Selling price of 2nd book
= 85% x 35
=
85100 x 35
= $29.75
Amount that Winnie paid more for the 1st book than the 2nd book
= 35.10 - 29.75
= $5.35
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 10% |
- 15% |
|
Sale price |
90%
|
85%
|
|
Compare 1st book and 2nd book |
1 u + $4.75 |
1 u |
$43.85 |
(b)
Sale price of the 1st book = 1 u + 4.75
Sale price of the 2nd book = 1 u
Total amount that Ethan paid
= 1 u + 4.75 + 1 u
= 2 u + 4.75
2 u + 4.75 = 43.85
2 u = 43.85 - 4.75
2 u = 39.10
1 u = 39.10 ÷ 2 = 19.55
Sale price of the 1st book
= 1 u + 4.75
= $24.30
90% of the price = $24.30
100% of the price =
24.3090 x 100 = $27
Selling price of the 1st book before discount = $27
Answer(s): (a) $5.35; (b) $27