There were some oranges and passion fruits in Container M and Container N. In Container M, the ratio of the oranges to the number of passion fruits was 3 : 1. In Container N, the ratio of the number of oranges to the number of passion fruits was 3 : 1. There were 3 times as many fruits in Container M as in Container N. After another 72 passion fruits were put into Container N, the ratio of the number of oranges to the number of passion fruits in Container N became 1 : 3. How many fruits were there in Container M?

Container M		Container N
3x4 = 12 u		1x4 = 4 u
Oranges	Passion fruits	Oranges	Passion fruits
3x3	1x3	3	1
9 u	3 u	3 u	1 u

The total number of fruits in Container M is repeated.  Make the total number of fruits in Container M the same.  LCM of 3 and 4 is 12.

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

	Container M		Container N
	Oranges	Passion fruits	Oranges	Passion fruits
Before	9 u	3 u	3 u	1 u
Change				+ 72
After	9 u	3 u	1x3 = 3 u	3x3 = 9 u

Number of oranges in Container N remains unchanged.  Make the number of oranges in Container N the same.  LCM of 3 and 1 is 3.

Number of passion fruits put into Container N
= 9 u - 1 u
= 8 u

8 u = 72

1 u = 72 ÷ 8 = 9

Number of fruits in Container M
= 9 u + 3 u
= 12 u
= 12 x 9
= 108

Answer(s): 108