At first, Vincent, Tiffany and Caden had some mochi balls in the ratio 7 : 5 : 6 respectively. Vincent had 343 mochi balls. Then he gave all his mochi balls to Tiffany and Caden. After receiving the mochi balls from Vincent, Tiffany and Caden had the same number of mochi balls. How many mochi balls did Tiffany receive from Vincent?

	Vincent	Tiffany	Caden	Total
Before	7x1 = 7 u	5x1 = 5 u	6x1 = 6 u	18x1 = 18 u
Change	- 7 u	+ 7 u
After	0	1x9 = 9 u	1x9 = 9 u	2x9 = 18 u

The total number of mochi balls remains unchanged. Make the total number of mochi balls the same.  LCM of 2 and 18 is 18.

Total number of mochi balls = 18 u

Number of mochi balls that Tiffany had in the end 
= 18 u ÷ 2
= 9 u

Number of mochi balls that Vincent had at first = 7 u 

7 u = 343

1 u = 343 ÷ 7 = 49

Number of mochi balls that Tiffany received from Vincent
= 9 u - 5 u
= 4 u
= 4 x 49
= 196

Answer(s): 196