Fabian, Oscar and Andy have some stickers. The ratios of their stickers are as follows:

Fabian : (Fabian + Oscar + Andy) = 2 : 5
Oscar : (Fabian + Andy) = 1 : 3

Andy has 10 stickers more than Oscar. In the end, Andy gives away all he has to Oscar and Fabian so that both Oscar and Fabian end up with the same number of stickers, how many stickers has Oscar received from Andy?

Oscar	Andy	Fabian	Total
3x4		2x4	5x4
1x5	3x5		4x5
5 u	7 u	8 u	20 u

The total number of stickers is repeated.  Make the total number of stickers the same.  LCM of 5 and 4 is 20.

Number of stickers that Andy has more than Oscar
= 7 u - 5 u
= 2 u

2 u = 10

1 u = 10 ÷ 2 = 5

	Oscar	Andy	Fabian
Before	5 u	7 u	8 u
Change	+ 5 u	- 7 u	+ 2 u
After	10 u	0 u	10 u

Number of stickers that Oscar has received from Andy
= 10 u - 5 u 
= 5 u
= 5 x 5
= 25

Answer(s): 25