PSLE
A shop is having a book sale. The 1st book is at 5% discount. The 2nd book is at 30% discount. The price of the 2nd book should be equal or lower than the price of the 1st book.

1. Victoria's books were priced at $32 and $39. How much more did she pay for the 1st book than the 2nd book? 
2. Bobby paid a total of $41.05 for his two books. He paid $10.25 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% $32
Discount	- 5%	- 30%
Sale price	95%	70%	?

(a)
Selling price of the 1st book
= 95% x 39
= ⁹⁵₁₀₀ x 39
= $37.05

Selling price of 2nd book
= 70% x 32
= ⁷⁰₁₀₀ x 32
= $22.40

Amount that Victoria paid more for the 1st book than the 2nd book
= 37.05 - 22.40
= $14.65

	1st book	2nd book	Total amount
Original price	100%	100%
Discount	- 5%	- 30%
Sale price	95%	70%
Compare 1st book and 2nd book	1 u + $10.25	1 u	$41.05

(b)
Sale price of the 1st book = 1 u + 10.25
Sale price of the 2nd book = 1 u

Total amount that Bobby paid
= 1 u + 10.25 + 1 u
= 2 u + 10.25

2 u + 10.25 = 41.05
2 u = 41.05 - 10.25
2 u = 30.80

1 u = 30.80 ÷ 2 = 15.40

Sale price of the 1st book
= 1 u + 10.25
= $25.65

95% of the price = $25.65
100% of the price = ^25.65₉₅ x 100 = $27

Selling price of the 1st book before discount = $27

Answer(s): (a) $14.65; (b) $27