Zara, Barbara, Pamela and Kylie jointly contributed to the cost of a present for their brother. Zara's contribution is ³₇ of the total contribution made by the four girls. The ratio of Kylie's contribution to the total of Barbara's and Pamela's contribution is 3 : 1. What is the total contribution by the four girls if Barbara's contribution is ¹₇ of Pamela's contribution and the total amount contributed by Zara and Kylie is $144?

Zara	Barbara	Pamela	Kylie	Total
3x8	4x8			7x8
	1x8		3x8
	1x1	7x1
24 u	1 u	7 u	24 u	56 u

Working backwards.

Total amount that Barbara and Pamela had is the combined repeated identity.
LCM of 1 and 8 = 8

Total amount that Barbara, Pamela and Kylie had is the next combined repeated identity.
LCM of 4 and 8 = 32 

Total amount contributed by Zara and Kylie
= 24 u + 24 u
= 48 u

48 u = 144

1 u = 144 ÷ 48 = $3

Total contribution by the four girls
= 56 u
= 56 x 3
= $168

Answer(s): $168