PSLE A book shop is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 10% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Nora and Cole each bought two books at the sale.
- Nora's books were priced at $17 and $23. How much less did she pay for the 2nd book than the 1st book?
- Cole paid a total of $56.65 for his two books. He paid $9.85 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% $17 |
|
Discount |
- 5% |
- 10% |
|
Sale price |
95% |
90% |
? |
(a)
Selling price of the 1st book
= 95% x 23
=
95100 x 23
= $21.85
Selling price of 2nd book
= 90% x 17
=
90100 x 17
= $15.30
Amount that Nora paid less for the 2nd book than the 1st book
= 21.85 - 15.30
= $6.55
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 10% |
|
Sale price |
95%
|
90%
|
|
Compare 1st book and 2nd book |
1 u + $9.85 |
1 u |
$56.65 |
(b)
Sale price of the 1st book = 1 u + 9.85
Sale price of the 2nd book = 1 u
Total amount that Cole paid
= 1 u + 9.85 + 1 u
= 2 u + 9.85
2 u + 9.85 = 56.65
2 u = 56.65 - 9.85
2 u = 46.80
1 u = 46.80 ÷ 2 = 23.40
Sale price of the 1st book
= 1 u + 9.85
= $33.25
95% of the price = $33.25
100% of the price =
33.2595 x 100 = $35
Selling price of the 1st book before discount = $35
Answer(s): (a) $6.55; (b) $35