In a group of cows and hens, the number of legs are 8 more than twice the number of heads. The number of cows is :	Choose the most appropriate option
A) 5 B) 6 C) 7 D) 10 E) 4

Rationale: let no of cows be x , no of hens be y . so heads = x + y legs = 4 x + 2 y now , 4 x + 2 y = 2 ( x + y ) + 8 2 x = 8 x = 4 . answer : e
Answer: E