PSLE A stationery kiosk is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 40% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Emily and Andy each bought two books at the sale.
- Emily's books were priced at $21 and $23. How much less did she pay for the 2nd book than the 1st book?
- Andy paid a total of $32.30 for his two books. He paid $11.90 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% $21 |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85% |
60% |
? |
(a)
Selling price of the 1st book
= 85% x 23
=
85100 x 23
= $19.55
Selling price of 2nd book
= 60% x 21
=
60100 x 21
= $12.60
Amount that Emily paid less for the 2nd book than the 1st book
= 19.55 - 12.60
= $6.95
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85%
|
60%
|
|
Compare 1st book and 2nd book |
1 u + $11.90 |
1 u |
$32.30 |
(b)
Sale price of the 1st book = 1 u + 11.90
Sale price of the 2nd book = 1 u
Total amount that Andy paid
= 1 u + 11.90 + 1 u
= 2 u + 11.90
2 u + 11.90 = 32.30
2 u = 32.30 - 11.90
2 u = 20.40
1 u = 20.40 ÷ 2 = 10.20
Sale price of the 1st book
= 1 u + 11.90
= $22.10
85% of the price = $22.10
100% of the price =
22.1085 x 100 = $26
Selling price of the 1st book before discount = $26
Answer(s): (a) $6.95; (b) $26