Joelle had some money. She spent 25% on rent and 10% of her remaining money on a blazer. She had $405 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 Joelle's amount left after she spent on rent
= 100% - 25%
= 75%

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

Fraction of Joelle's amount left
= 90% x 75% 
= ⁹⁰₁₀₀ x ⁷⁵₁₀₀
= ²⁷₄₀

Total amount that Joelle had = 40 u
Amount that Joelle had left = 27 u

27 u = 405

1 u = 405 ÷ 27 = 15

Amount that Joelle had at first
= 40 u
= 40 x 15
= $600

(b)
Fraction of Joelle's amount spent on the blazer
= 10% x 75% 
= ¹⁰₁₀₀ x ⁷⁵₁₀₀ 
= ³₄₀

Amount that Joelle spent on the blazer
= 3 u
= 3 x 15
= $45

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

75% of the price of the blazer = 45
1% of the price of the blazer = 45 ÷ 75 = 0.6
100% of the price of the blazer = 100 x 0.6 = 60

Original price of the blazer = $60

Answer(s): (a) $600; (b) $60