PSLE
Risa wanted to buy a vest. She saw a black vest on sale at 25% discount and a brown vest at 40% discount. Both vests had the same original price before the discounts. To buy the black vest, Risa would need $9.60 more that what she had. So Risa bought the brown vest. After that, she had $9 left.

1. What was the original price of the black vest?
2. How much money did Risa have at first?

	Black vest	Brown vest
Before	100%	100%
Change	- 25%	- 40%
After	75%	60%

(a)
Difference in the discount between the black vest and the brown vest
= 40% - 25%
= 15%

Additional amount that Risa needed to pay if she would buy the black vest
= 9.60 + 9
= $18.60

15% →  18.60
100% → ^18.60₁₅ x 100 = 124

Original price of the black vest = $124

(b)
Price of the brown vest after discount in percentage
= 100% - 40%
= 60%

Price of the brown vest after discount
= ⁶⁰₁₀₀ x 124
= $74.40

Amount that Risa had at first
= 74.40 + 9
= $83.40

Answer(s): (a) $124; (b) $83.40