A man has some hens and cows. If the number of heads be 46 and the number of feet equals 140, then the number of hens will be:  Choose the correct choice from the following options.
A) 22  B) 23  C) 24  D) 26  E) 28

Rationale: "let hens be x and cows be y now , feet : x * 2 + y * 4 = 140 heads : x * 1 + y * 1 = 46 implies , 2 x + 4 y = 140 and x + y = 46 solving these two equations , we get x = 22 and y = 24 therefore , hens are 22 . answer : a"
Answer: A