PSLE A book shop is having a book sale.
The 1st book is at 10% discount.
The 2nd book is at 35% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Penelope and Perry each bought two books at the sale.
- Penelope's books were priced at $4 and $11. How much less did she pay for the 2nd book than the 1st book?
- Perry paid a total of $51.25 for his two books. He paid $13.55 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% $11 |
100% $4 |
|
Discount |
- 10% |
- 35% |
|
Sale price |
90% |
65% |
? |
(a)
Selling price of the 1st book
= 90% x 11
=
90100 x 11
= $9.90
Selling price of 2nd book
= 65% x 4
=
65100 x 4
= $2.60
Amount that Penelope paid less for the 2nd book than the 1st book
= 9.90 - 2.60
= $7.30
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 10% |
- 35% |
|
Sale price |
90%
|
65%
|
|
Compare 1st book and 2nd book |
1 u + $13.55 |
1 u |
$51.25 |
(b)
Sale price of the 1st book = 1 u + 13.55
Sale price of the 2nd book = 1 u
Total amount that Perry paid
= 1 u + 13.55 + 1 u
= 2 u + 13.55
2 u + 13.55 = 51.25
2 u = 51.25 - 13.55
2 u = 37.70
1 u = 37.70 ÷ 2 = 18.85
Sale price of the 1st book
= 1 u + 13.55
= $32.40
90% of the price = $32.40
100% of the price =
32.4090 x 100 = $36
Selling price of the 1st book before discount = $36
Answer(s): (a) $7.30; (b) $36