There were some passion fruits and starfruits in Container M and Container N. In Container M, the ratio of the passion fruits to the number of starfruits was 6 : 1. In Container N, the ratio of the number of passion fruits to the number of starfruits was 4 : 3. There were 2 times as many fruits in Container M as in Container N. After another 30 starfruits were put into Container N, the ratio of the number of passion fruits to the number of starfruits in Container N became 1 : 2. How many fruits were there in Container N in the end?

Container M		Container N
2x7 = 14 u		1x7 = 7 u
Passion fruits	Starfruits	Passion fruits	Starfruits
6x2	1x2	4	3
12 u	2 u	4 u	3 u

The total number of fruits in Container M is repeated.  Make the total number of fruits in Container M the same.  LCM of 2 and 7 is 14.

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 7 is 7.

	Container M		Container N
	Passion fruits	Starfruits	Passion fruits	Starfruits
Before	12 u	2 u	4 u	3 u
Change				+ 30
After	12 u	2 u	1x4 = 4 u	2x4 = 8 u

Number of passion fruits in Container N remains unchanged.  Make the number of passion fruits in Container N the same.  LCM of 4 and 1 is 4.

Number of starfruits put into Container N
= 8 u - 3 u
= 5 u

5 u = 30

1 u = 30 ÷ 5 = 6

Number of fruits in Container N in the end
= 4 u + 8 u
= 12 u
= 12 x 6
= 72

Answer(s): 72