There were some kiwis and oranges in Box X and Box Y. In Box X, the ratio of the kiwis to the number of oranges was 3 : 1. In Box Y, the ratio of the number of kiwis to the number of oranges was 3 : 1. There were 2 times as many fruits in Box X as in Box Y. After another 40 oranges were put into Box Y, the ratio of the number of kiwis to the number of oranges in Box Y became 1 : 3. How many fruits were there in Box Y in the end?

Box X		Box Y
2x4 = 8 u		1x4 = 4 u
Kiwis	Oranges	Kiwis	Oranges
3x2	1x2	3	1
6 u	2 u	3 u	1 u

The total number of fruits in Box X is repeated.  Make the total number of fruits in Box X the same.  LCM of 2 and 4 is 8.

The total number of fruits in Box Y at first is repeated.  Make the total number of fruits in Box Y the same.  LCM of 1 and 4 is 4.

	Box X		Box Y
	Kiwis	Oranges	Kiwis	Oranges
Before	6 u	2 u	3 u	1 u
Change				+ 40
After	6 u	2 u	1x3 = 3 u	3x3 = 9 u

Number of kiwis in Box Y remains unchanged.  Make the number of kiwis in Box Y the same.  LCM of 3 and 1 is 3.

Number of oranges put into Box Y
= 9 u - 1 u
= 8 u

8 u = 40

1 u = 40 ÷ 8 = 5

Number of fruits in Box Y in the end
= 3 u + 9 u
= 12 u
= 12 x 5
= 60

Answer(s): 60