80% of Jen's amount was $665 more than Gabriel's amount. When Jen spent 55% of her amount and Gabriel spent 20% of his amount, they had the same amount of amount left. Find the amount that Gabriel had at first.

	80% of Jen's amount	Jen's amount	Gabriel's amount
Before	64 u	80 u	45 u
Change		- 44 u (- 55%)	- 9 u (- 20%)
After		36 u	36 u

Percentage of Jen's amount left
= 100% - 55%
= 45%

Percentage of Gabriel's amount left
= 100% - 20%
= 80%

45% = ⁴⁵₁₀₀ = ⁹₂₀
80% = ⁸⁰₁₀₀ = ⁴₅

The amounts of amount that Jen and Gabriel had left were the same.
Make the numerators the same.

⁹₂₀ of Jen's amount = ⁴₅ of Gabriel's amount
³⁶₈₀ of Jen's amount = ³⁶₄₅ of Gabriel's amount

Amount that Jen had = 80 u

80% of the amount that Jen had
= 80 u x 80%
= 80 u x ⁸⁰₁₀₀
= 64 u

Difference between 80% of Jen's amount and Gabriel's amount
= 64 u - 45 u 
= 19 u

19 u = 665
1 u = 665 ÷ 19 = 35

Amount that Gabriel had at first
= 45 u
= 45 x 35
= $1575

Answer(s): $1575