Fiona had some money. She spent 20% on books and 10% of her remaining money on a blazer. She had $270 left.

1. How much did she have at first?
2. If the blazer was bought at a 25% discount, what was the original price of the blazer?

(a)
Percent of Fiona's amount left after she spent on books
= 100% - 20%
= 80%

Percent of Fiona's remaining amount left after she spent on the blazer
= 100% - 10%
= 90%

Fraction of Fiona's amount left
= 90% x 80% 
= ⁹⁰₁₀₀ x ⁸⁰₁₀₀
= ¹⁸₂₅

Total amount that Fiona had = 25 u
Amount that Fiona had left = 18 u

18 u = 270

1 u = 270 ÷ 18 = 15

Amount that Fiona had at first
= 25 u
= 25 x 15
= $375

(b)
Fraction of Fiona's amount spent on the blazer
= 10% x 80% 
= ¹⁰₁₀₀ x ⁸⁰₁₀₀ 
= ²₂₅

Amount that Fiona spent on the blazer
= 2 u
= 2 x 15
= $30

Discounted price of the blazer in percent
= 100% - 25%
= 75%

75% of the price of the blazer = 30
1% of the price of the blazer = 30 ÷ 75 = 0.4
100% of the price of the blazer = 100 x 0.4 = 40

Original price of the blazer = $40

Answer(s): (a) $375; (b) $40