PSLE A store is having a book sale. The 1st book is at 5% discount. The 2nd book is at 20% discount. The price of the 2nd book should be equal or lower than the price of the 1st book.
- Sabrina's books were priced at $27 and $39. How much less did she pay for the 2nd book than the 1st book?
- Sean paid a total of $47.70 for his two books. He paid $9.30 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% $39 |
100% $27 |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95% |
80% |
? |
(a)
Selling price of the 1st book
= 95% x 39
=
95100 x 39
= $37.05
Selling price of 2nd book
= 80% x 27
=
80100 x 27
= $21.60
Amount that Sabrina paid less for the 2nd book than the 1st book
= 37.05 - 21.60
= $15.45
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95%
|
80%
|
|
Compare 1st book and 2nd book |
1 u + $9.30 |
1 u |
$47.70 |
(b)
Sale price of the 1st book = 1 u + 9.30
Sale price of the 2nd book = 1 u
Total amount that Sean paid
= 1 u + 9.30 + 1 u
= 2 u + 9.30
2 u + 9.30 = 47.70
2 u = 47.70 - 9.30
2 u = 38.40
1 u = 38.40 ÷ 2 = 19.20
Sale price of the 1st book
= 1 u + 9.30
= $28.50
95% of the price = $28.50
100% of the price =
28.5095 x 100 = $30
Selling price of the 1st book before discount = $30
Answer(s): (a) $15.45; (b) $30