Charlie, Bryan and Adam have $1235.
After Charlie spends ⁵₇ of his money,
Bryan spends ²₉ 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	7 x 7 = 49 u	9 x 2 = 18 u	2 x 14 = 28 u
Change	- 5 x 7 = - 35 u	- 2 x 2 = - 4 u	- 1 x 14 = - 14 u
After	2 x 7 =  14 u	7 x 2 = 14 u	1 x 14 = 14 u

The lowest common multiple of 2, 7 and 1 is 14.

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

Fraction of the amount left after Bryan spends his money
= 1 - ²₉
= ⁷₉

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

Make the numerators the same.
2 x 77 x 7 of Charlie's amount = 7 x 29 x 2 of Bryan's amount = 1 x 142 x 14 of Adam's amount
1449 of Charlie's amount = 1418 of Bryan's amount = 1428 of Adam's amount

Total amount that they have at first
= 49 u + 18 u + 28 u
= 95 u

95 u = 1235

1 u = 1235 ÷ 95 = 13

Amount that Charlie spends
= 49 u - 14 u
= 35 u

Amount that Bryan spends
= 18 u - 14 u
= 4 u

Amount that Adam spends
= 28 u - 14 u
= 14 u

Amount that they spend
= 35 u + 4 u + 14 u
= 53 u
= 53 x 13
= $689

Answer(s): $689