20% of Lee's savings was $6 more than 30% of Ahmad's savings. After Lee spent ²₅ of his savings and Ahmad spent 40% of his savings, Ahmad had $33 less than Lee. How much was Ahmad's saving at first?

	Ahmad	Lee
Before	10 u	15 u + 30
Change	- 4 u	- 6 u - 12
After	6 u	9 u + 18
Comparing Ahmad and Lee in the end		33 more

20% = ²⁰₁₀₀ = ¹₅

30% = ³⁰₁₀₀ = ³₁₀

¹₅ Lee = ³₁₀ Ahmad + 6 

Make the numerators the same. LCM of 1 and 3 is 3.
 
1x35x3 Lee = 3x110x1 Ahmad + 6 
315 Lee = 310 Ahmad + 6 

Simplify the fractions.
¹₁₅ Lee = ¹₁₀ Ahmad + 2

Let ¹₁₀ Ahmad be 1 u.

Ahmad's savings at first = 10 u

¹₁₅ Lee = ¹₁₀ Ahmad + 2
Let ¹₁₅ Lee be 1 u + 2.

Lee's savings at first
= 15 x (1 u + 2) 
= 15 u + 30

Savings that Ahmad spent
= 40% x 10 u
= ⁴⁰₁₀₀ x 10 u
= 4 u

Savings that Lee spent 
= ²₅ x (15 u + 30)
= 6 u + 12 

Ahmad had $33 less than Lee in the end. If another $33 was given to Ahmad, the amount that each had in the end would be the same.

9 u + 18 = 6 u + 33 
9 u - 6 u = 33 - 18
3 u = 15

1 u = 15 ÷ 3 = 5

Savings that Ahmad had at first
= 10 u 
= 10 x 5
= $50

Answer(s): $50