A fruit seller sells only passion fruits and chikoos. The ratio of passion fruits to chikoos is 3 : 4. A total of 78 fruits are added. The number of passion fruits becomes 4 times as many as before and the number of chikoos becomes 2 times as many as before. How many fruits are there in the end?

	Comparing passion fruits at first and in the end	Passion Fruits	Chikoos	Comparing chikoos at first and in the end
Before	1x3 = 3 u	3 u	4 u	1x4 = 4 u
Change		+ 78
After	4x3 = 12 u	12 u	8 u	2x4 = 8 u

The number of chikoos at first is repeated.  Make the number of chikoos at first the same.  LCM of 1 and 4 is 4.

The number of passion fruits at first is repeated. Make the number of passion fruits at first the same. LCM of 1 and 3 is 3.

Number of fruits at first
= 3 u + 4 u
= 7 u

Number of fruits in the end
= 12 u + 8 u
= 20 u

Number of fruits added
= 20 u - 7 u 
= 13 u

13 u = 78

1 u = 78 ÷ 13 = 6

Number of fruits in the end
= 20 u
= 20 x 6
= 120

Answer(s): 120