90% of Cindy's amount was $777 more than Ahmad's amount. When Cindy spent 65% of her amount and Ahmad spent 20% of his amount, they had the same amount of amount left. Find the amount that Ahmad had at first.

	90% of Cindy's amount	Cindy's amount	Ahmad's amount
Before	72 u	80 u	35 u
Change		- 52 u (- 65%)	- 7 u (- 20%)
After		28 u	28 u

Percentage of Cindy's amount left
= 100% - 65%
= 35%

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

35% = ³⁵₁₀₀ = ⁷₂₀
80% = ⁸⁰₁₀₀ = ⁴₅

The amounts of amount that Cindy and Ahmad had left were the same.
Make the numerators the same.

⁷₂₀ of Cindy's amount = ⁴₅ of Ahmad's amount
²⁸₈₀ of Cindy's amount = ²⁸₃₅ of Ahmad's amount

Amount that Cindy had = 80 u

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

Difference between 90% of Cindy's amount and Ahmad's amount
= 72 u - 35 u 
= 37 u

37 u = 777
1 u = 777 ÷ 37 = 21

Amount that Ahmad had at first
= 35 u
= 35 x 21
= $735

Answer(s): $735