Tina, Vanessa, Yen and Hazel jointly contributed to the cost of a present for their schoolmate. Tina's contribution is ⁴₅ of the total contribution made by the four girls. The ratio of Hazel's contribution to the total of Vanessa's and Yen's contribution is 4 : 1. What is the total contribution by the four girls if Vanessa's contribution is ¹₄ of Yen's contribution and the total amount contributed by Tina and Hazel is $240?

Tina	Vanessa	Yen	Hazel	Total
4x25	1x25			5x25
	1x5		4x5
	1x1	4x1
100 u	1 u	4 u	20 u	125 u

Working backwards.

Total amount that Vanessa and Yen had is the combined repeated identity.
LCM of 1 and 5 = 5

Total amount that Vanessa, Yen and Hazel had is the next combined repeated identity.
LCM of 1 and 25 = 25 

Total amount contributed by Tina and Hazel
= 100 u + 20 u
= 120 u

120 u = 240

1 u = 240 ÷ 120 = $2

Total contribution by the four girls
= 125 u
= 125 x 2
= $250

Answer(s): $250