10% of Andy's savings was $36 more than 30% of Bryan's savings. After Andy spent ¹₂ of his savings and Bryan spent 40% of his savings, Bryan had $216 less than Andy. How much was Bryan's saving at first?

	Bryan	Andy
Before	10 u	30 u + 360
Change	- 4 u	- 15 u - 180
After	6 u	15 u + 180
Comparing Bryan and Andy in the end		216 more

10% = ¹⁰₁₀₀ = ¹₁₀

30% = ³⁰₁₀₀ = ³₁₀

¹₁₀ Andy = ³₁₀ Bryan + 36 

Make the numerators the same. LCM of 1 and 3 is 3.
 
1x310x3 Andy = 3x110x1 Bryan + 36 
330 Andy = 310 Bryan + 36 

Simplify the fractions.
¹₃₀ Andy = ¹₁₀ Bryan + 12

Let ¹₁₀ Bryan be 1 u.

Bryan's savings at first = 10 u

¹₃₀ Andy = ¹₁₀ Bryan + 12
Let ¹₃₀ Andy be 1 u + 12.

Andy's savings at first
= 30 x (1 u + 12) 
= 30 u + 360

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

Savings that Andy spent 
= ¹₂ x (30 u + 360)
= 15 u + 180 

Bryan had $216 less than Andy in the end. If another $216 was given to Bryan, the amount that each had in the end would be the same.

15 u + 180 = 6 u + 216 
15 u - 6 u = 216 - 180
9 u = 36

1 u = 36 ÷ 9 = 4

Savings that Bryan had at first
= 10 u 
= 10 x 4
= $40

Answer(s): $40