90% of Kathy's amount was $459 more than Glen's amount. When Kathy spent 55% of her amount and Glen spent 20% of his amount, they had the same amount of amount left. Find the amount that Glen had at first.

	90% of Kathy's amount	Kathy's amount	Glen's amount
Before	72 u	80 u	45 u
Change		- 44 u (- 55%)	- 9 u (- 20%)
After		36 u	36 u

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

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

45% = ⁴⁵₁₀₀ = ⁹₂₀
80% = ⁸⁰₁₀₀ = ⁴₅

The amounts of amount that Kathy and Glen had left were the same.
Make the numerators the same.

⁹₂₀ of Kathy's amount = ⁴₅ of Glen's amount
³⁶₈₀ of Kathy's amount = ³⁶₄₅ of Glen's amount

Amount that Kathy had = 80 u

90% of the amount that Kathy had
= 80 u x 90%
= 80 u x ⁹⁰₁₀₀
= 72 u

Difference between 90% of Kathy's amount and Glen's amount
= 72 u - 45 u 
= 27 u

27 u = 459
1 u = 459 ÷ 27 = 17

Amount that Glen had at first
= 45 u
= 45 x 17
= $765

Answer(s): $765