The ratio of the number of geese in Farm B to the number of geese in Farm C was 3 : 10. There were 70 fewer geese in Farm B than in Farm C. When 7 geese escaped from Farm C, the farmer in Farm C bought another 17 geese. What was the new ratio of the number of geese in Farm B to the number of geese in Farm C in the end? Give your answer in the simplest form.
| |
Farm B |
Farm C |
| Before |
3 u |
10 u |
| Change 1 |
|
- 7 |
| Change 2 |
|
+ 17 |
| After |
3 u |
10 u + 10 |
Number of fewer geese in Farm B than Farm C
= 10 u - 3 u
= 7 u
7 u = 70
1 u = 70 ÷ 7 = 10
Number of geese in Farm B
= 3 u
= 10 x 3
= 30
Number of geese in Farm C
= 10 u
= 10 x 10
= 100
New number of geese in Farm C
= 10 u + 10
= 100 + 10
= 110
Farm B : Farm C
30 : 110
(÷ 10)3 : 11
Answer(s): 3 : 11
