20% of Irene's amount was $2304 less than Archie's amount. When Irene spent 30% of her amount and Archie spent 70% of his amount, they had the same amount of amount left. Find the amount that Archie had at first.

	Irene	Archie
Before	30 u	70 u
Change	- 9 u	- 49 u
After	21 u	21 u

Percentage of Irene's amount left
= 100% - 30%
= 70%

Percentage of Archie's amount left
= 100% - 70%
= 30%

70% = ⁷⁰₁₀₀ = ⁷₁₀
30% = ³⁰₁₀₀ = ³₁₀

The amounts of amount that Irene and Archie had left were the same. Make the numerators the same.

⁷₁₀ of Irene's amount = ³₁₀ of Archie's amount
²¹₃₀ of Irene's amount = ²¹₇₀ of Archie's amount

Amount that Irene had = 30 u

20% of the amount that Irene had
= 20% x 30 u
= ²⁰₁₀₀ x 30 u
= 6 u

Difference between Archie's amount and 20% of Irene's amount
= 70 u - 6 u
= 64 u

64 u = 2304

1 u = 2304 ÷ 64 = 36

Amount that Archie had at first
= 70 u
= 70 x 36
= $2520

Answer(s): $2520