A fruit seller sells only peaches and mangoes. The ratio of peaches to mangoes is 2 : 5. A total of 323 fruits are added. The number of peaches becomes 3 times as many as before and the number of mangoes becomes 4 times as many as before. How many fruits are there at first?

	Comparing peaches at first and in the end	Peaches	Mangoes	Comparing mangoes at first and in the end
Before	1x2 = 2 u	2 u	5 u	1x5 = 5 u
Change		+ 323
After	3x2 = 6 u	6 u	20 u	4x5 = 20 u

The number of mangoes at first is repeated.  Make the number of mangoes at first the same.  LCM of 1 and 5 is 5.

The number of peaches at first is repeated. Make the number of peaches at first the same. LCM of 1 and 2 is 2.

Number of fruits at first
= 2 u + 5 u
= 7 u

Number of fruits in the end
= 6 u + 20 u
= 26 u

Number of fruits added
= 26 u - 7 u 
= 19 u

19 u = 323

1 u = 323 ÷ 19 = 17

Number of fruits at first
= 7 u
= 7 x 17
= 119

Answer(s): 119