A man has some hens and cows. If the number of heads be 42 and the number of feet equals 124, then the number of hens will be
Choose the correct choice from the following:  A) 22  B) 24  C) 26  D) 20  E) 28

Rationale: "explanation : let number of hens = h and number of cows = c number of heads = 42 = > h + c = 42 - - - ( equation 1 ) number of feet = 124 = > 2 h + 4 c = 124 = > h + 2 c = 62 - - - ( equation 2 ) ( equation 2 ) - ( equation 1 ) gives 2 c - c = 62 - 42 = > c = 20 substituting the value of c in equation 1 , we get h + 22 = 42 = > h = 42 - 20 = 22 i . e . , number of hens = 22 answer : a"
Answer: A