Irene had some money. She spent 40% on food and 25% of her remaining money on a blouse. She had $36 left.

1. How much did she have at first?
2. If the blouse was bought at a 20% discount, what was the original price of the blouse?

(a)
Percent of Irene's amount left after she spent on food
= 100% - 40%
= 60%

Percent of Irene's remaining amount left after she spent on the blouse
= 100% - 25%
= 75%

Fraction of Irene's amount left
= 75% x 60% 
= ⁷⁵₁₀₀ x ⁶⁰₁₀₀
= ⁹₂₀

Total amount that Irene had = 20 u
Amount that Irene had left = 9 u

9 u = 36

1 u = 36 ÷ 9 = 4

Amount that Irene had at first
= 20 u
= 20 x 4
= $80

(b)
Fraction of Irene's amount spent on the blouse
= 25% x 60% 
= ²⁵₁₀₀ x ⁶⁰₁₀₀ 
= ³₂₀

Amount that Irene spent on the blouse
= 3 u
= 3 x 4
= $12

Discounted price of the blouse in percent
= 100% - 20%
= 80%

80% of the price of the blouse = 12
1% of the price of the blouse = 12 ÷ 80 = 0.15
100% of the price of the blouse = 100 x 0.15 = 15

Original price of the blouse = $15

Answer(s): (a) $80; (b) $15