At first, Seth, Gillian and Dylan had some chocolate bars in the ratio 7 : 5 : 6 respectively. Seth had 350 chocolate bars. Then he gave all his chocolate bars to Gillian and Dylan. After receiving the chocolate bars from Seth, Gillian and Dylan had the same number of chocolate bars. How many chocolate bars did Gillian receive from Seth?

	Seth	Gillian	Dylan	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 chocolate bars remains unchanged. Make the total number of chocolate bars the same.  LCM of 2 and 18 is 18.

Total number of chocolate bars = 18 u

Number of chocolate bars that Gillian had in the end 
= 18 u ÷ 2
= 9 u

Number of chocolate bars that Seth had at first = 7 u 

7 u = 350

1 u = 350 ÷ 7 = 50

Number of chocolate bars that Gillian received from Seth
= 9 u - 5 u
= 4 u
= 4 x 50
= 200

Answer(s): 200