The ratio of the number of geese in Farm C to the number of geese in Farm D was 5 : 7. There were 40 fewer geese in Farm C than in Farm D. When 11 geese escaped from Farm D, the farmer in Farm D bought another 16 geese. What was the new ratio of the number of geese in Farm C to the number of geese in Farm D in the end? Give your answer in the simplest form.
| |
Farm C |
Farm D |
| Before |
5 u |
7 u |
| Change 1 |
|
- 11 |
| Change 2 |
|
+ 16 |
| After |
5 u |
7 u + 5 |
Number of fewer geese in Farm C than Farm D
= 7 u - 5 u
= 2 u
2 u = 40
1 u = 40 ÷ 2 = 20
Number of geese in Farm C
= 5 u
= 20 x 5
= 100
Number of geese in Farm D
= 7 u
= 20 x 7
= 140
New number of geese in Farm D
= 7 u + 5
= 140 + 5
= 145
Farm C : Farm D
100 : 145
(÷ 5)20 : 29
Answer(s): 20 : 29
