Charlie, Adam and Bryan have $910.
After Charlie spends ²₅ of his money,
Adam spends ²₃ of his money and
Bryan spends ²₇ of his money,
they have equal amount of money left.
Find the total amount that the 3 children spend.

	Charlie	Adam	Bryan
Before	5 x 5 = 25 u	3 x 15 = 45 u	7 x 3 = 21 u
Change	- 2 x 5 = - 10 u	- 2 x 15 = - 30 u	- 2 x 3 = - 6 u
After	3 x 5 =  15 u	1 x 15 = 15 u	5 x 3 = 15 u

The lowest common multiple of 3, 1 and 5 is 15.

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

Fraction of the amount left after Adam spends his money
= 1 - ²₃
= ¹₃

Fraction of the amount left after Bryan spends his money
= 1 - ²₇
= ⁵₇

Make the numerators the same.
3 x 55 x 5 of Charlie's amount = 1 x 153 x 15 of Adam's amount = 5 x 37 x 3 of Bryan's amount
1525 of Charlie's amount = 1545 of Adam's amount = 1521 of Bryan's amount

Total amount that they have at first
= 25 u + 45 u + 21 u
= 91 u

91 u = 910

1 u = 910 ÷ 91 = 10

Amount that Charlie spends
= 25 u - 15 u
= 10 u

Amount that Adam spends
= 45 u - 15 u
= 30 u

Amount that Bryan spends
= 21 u - 15 u
= 6 u

Amount that they spend
= 10 u + 30 u + 6 u
= 46 u
= 46 x 10
= $460

Answer(s): $460