At a farm, the ratio of the number of chickens to the number of sheep was 5:2. After the farmer sold 15 chickens, there was an equal number of chickens and sheep. How many chickens and sheep were there at the farm in the end?
My work:
Number of chickens = C
Number of Sheep = S
*We know (C/S) = (5/2)
*We know that the farmer sold 15 chickens and then had equal number of both animals.
So C – 15 = S
Then I plugged C – 15 = S into (C/S) = (5/2)
So I got C = 25. (So I'm guessing there where 25 chickens before?)
Since we know that there were 25 chickens before, I pluged C = 25 into C – 15 = S
So 25 – 15 = S
So, we know that there are 10 Chickens and 10 Sheep. So the answer should be 20 total?
If I'm correct, is there a better way to do this?
Best Answer
Initially you have $5$ units of chickens and $2$ units of sheep.
After selling, we have $2$ units of chickens and $2$ units of sheep.
So $3$ units is equal to $15$ animals and each unit represents $5$ animals.
In the end we have $4 \times 5 = 20$ animals. $10$ chickens and $10$ sheep.