The ratio of the number of chickens in Farm F to the number of chickens in Farm G was 5 : 7. There were 70 more chickens in Farm G than in Farm F. When 10 chickens escaped from Farm G, the farmer in Farm G bought another 20 chickens. What was the new ratio of the number of chickens in Farm F to the number of chickens in Farm G in the end? Give your answer in the simplest form.

	Farm F	Farm G
Before	5 u	7 u
Change 1		- 10
Change 2		+ 20
After	5 u	7 u + 10

Number of more chickens in Farm G than Farm F
= 7 u - 5 u
= 2 u

2 u = 70

1 u = 70 ÷ 2 = 35

Number of chickens in Farm F
= 5 u
= 35 x 5
= 175

Number of chickens in Farm G
= 7 u
= 35 x 7
= 245

New number of chickens in Farm G
= 7 u + 10
= 245 + 10
= 255

Farm F : Farm G
175 : 255 _{(÷ 5)}
35 : 51

Answer(s): 35 : 51