Question

in a group of cows and hens, the number of legs is 16 more then thrice the number of heads.the possible number of cows and hens are respectively a)20,4 b)4,20 c)18,6 d)6,18​

Answer 1

Let the number of cows be x and the number of hens be y.

Then, 4x + 2y = 2 (x + y) + 14 ⇔ 4x + 2y = 2x + 2y + 14 ⇔ 2x = 14 ⇔ x = 7.

Answer 2

● The possible number of cows and hens according to above given question are 20 and 4 respectively.

● No of heads is no of cows + no of hens.

According to question thrice the number of heads and 16 more is equal to 4 times cows and 2 times hens.

So 3 × ( no of cows + no of hens ) + 16 = 4 cows + 2 hens

3 cow + 3 hen + 16= 4 cow + 2 hens

Cow - hens = 16

by options, c=20 h=4