Charlie, Bryan and Adam have $430.
After Charlie spends ²₅ of his money,
Bryan spends ¹₁₀ of his money and
Adam spends ¹₂ of his money,
they have equal amount of money left.
Find the total amount that the 3 children spend.

	Charlie	Bryan	Adam
Before	5 x 3 = 15 u	10 x 1 = 10 u	2 x 9 = 18 u
Change	- 2 x 3 = - 6 u	- 1 x 1 = - 1 u	- 1 x 9 = - 9 u
After	3 x 3 =  9 u	9 x 1 = 9 u	1 x 9 = 9 u

The lowest common multiple of 3, 9 and 1 is 9.

Fraction of the amount left after Charlie spends his money
= 1 - ²₅
= ³₅

Fraction of the amount left after Bryan spends his money
= 1 - ¹₁₀
= ⁹₁₀

Fraction of the amount left after Adam spends his money
= 1 - ¹₂
= ¹₂

Make the numerators the same.
3 x 35 x 3 of Charlie's amount = 9 x 110 x 1 of Bryan's amount = 1 x 92 x 9 of Adam's amount
915 of Charlie's amount = 910 of Bryan's amount = 918 of Adam's amount

Total amount that they have at first
= 15 u + 10 u + 18 u
= 43 u

43 u = 430

1 u = 430 ÷ 43 = 10

Amount that Charlie spends
= 15 u - 9 u
= 6 u

Amount that Bryan spends
= 10 u - 9 u
= 1 u

Amount that Adam spends
= 18 u - 9 u
= 9 u

Amount that they spend
= 6 u + 1 u + 9 u
= 16 u
= 16 x 10
= $160

Answer(s): $160