90% of Natalie's amount was $4512 more than Vaidev's amount. When Natalie spent 65% of her amount and Vaidev spent 35% of his amount, they had the same amount of amount left. Find the amount that Vaidev had at first.

	90% of Natalie's amount	Natalie's amount	Vaidev's amount
Before	234 u	260 u	140 u
Change		- 169 u (- 65%)	- 49 u (- 35%)
After		91 u	91 u

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

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

35% = ³⁵₁₀₀ = ⁷₂₀
65% = ⁶⁵₁₀₀ = ¹³₂₀

The amounts of amount that Natalie and Vaidev had left were the same.
Make the numerators the same.

⁷₂₀ of Natalie's amount = ¹³₂₀ of Vaidev's amount
⁹¹₂₆₀ of Natalie's amount = ⁹¹₁₄₀ of Vaidev's amount

Amount that Natalie had = 260 u

90% of the amount that Natalie had
= 260 u x 90%
= 260 u x ⁹⁰₁₀₀
= 234 u

Difference between 90% of Natalie's amount and Vaidev's amount
= 234 u - 140 u 
= 94 u

94 u = 4512
1 u = 4512 ÷ 94 = 48

Amount that Vaidev had at first
= 140 u
= 140 x 48
= $6720

Answer(s): $6720