In a farm, there are cows and hens. The total number of heads is 50 and the total number of legs is 140. How many hens are there?
Show answer & explanation
Correct answer: C
Explanation
Total heads = 50
C+H=50
Total legs = 140
4C+2H=140
Now multiplying the first equation by 2 gives
2C+2H=100
Subtracting this from the second equation gives
(4C+2H)−(2C+2H)=140−100
2C=40
C=20
Now,
H=50−20=30