PSLE A book shop is having a book sale.
The 1st book is at 5% 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.
Min and Andy each bought two books at the sale.
- Min's books were priced at $25 and $28. How much less did she pay for the 2nd book than the 1st book?
- Andy paid a total of $44.45 for his two books. He paid $8.75 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% $28 |
100% $25 |
|
Discount |
- 5% |
- 15% |
|
Sale price |
95% |
85% |
? |
(a)
Selling price of the 1st book
= 95% x 28
=
95100 x 28
= $26.60
Selling price of 2nd book
= 85% x 25
=
85100 x 25
= $21.25
Amount that Min paid less for the 2nd book than the 1st book
= 26.60 - 21.25
= $5.35
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 15% |
|
Sale price |
95%
|
85%
|
|
Compare 1st book and 2nd book |
1 u + $8.75 |
1 u |
$44.45 |
(b)
Sale price of the 1st book = 1 u + 8.75
Sale price of the 2nd book = 1 u
Total amount that Andy paid
= 1 u + 8.75 + 1 u
= 2 u + 8.75
2 u + 8.75 = 44.45
2 u = 44.45 - 8.75
2 u = 35.70
1 u = 35.70 ÷ 2 = 17.85
Sale price of the 1st book
= 1 u + 8.75
= $26.60
95% of the price = $26.60
100% of the price =
26.6095 x 100 = $28
Selling price of the 1st book before discount = $28
Answer(s): (a) $5.35; (b) $28