Jane, Shiyun, Rachel and Erika jointly contributed to the cost of a present for their brother. Jane's contribution is ⁷₁₀ of the total contribution made by the four girls. The ratio of Erika's contribution to the total of Shiyun's and Rachel's contribution is 5 : 1. What is the total contribution by the four girls if Shiyun's contribution is ¹₄ of Rachel's contribution and the total amount contributed by Jane and Erika is $1425?

Jane	Shiyun	Rachel	Erika	Total
7x10	3x10			10x10
	1x5		5x5
	1x1	4x1
70 u	1 u	4 u	25 u	100 u

Working backwards.

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

Total amount that Shiyun, Rachel and Erika had is the next combined repeated identity.
LCM of 3 and 10 = 30 

Total amount contributed by Jane and Erika
= 70 u + 25 u
= 95 u

95 u = 1425

1 u = 1425 ÷ 95 = $15

Total contribution by the four girls
= 100 u
= 100 x 15
= $1500

Answer(s): $1500