A family has two children along with their parents. The average of the weights of the children and their mother is 50 kg. The average of the weights of the children and their father is 52 kg. If the weight of the father is 60 kg, then what is the weight of the mother?

Answer is (d). We know that – Average x Number of people = Total. Average of weight of two children and their mother (i.e. total 3 members) = 50. So, the sum of the weight of two children and mother = C1 + C2 + M = 50 × 3 = 150 ... (1) (where C1 and C2 are the weights of two children and M is the weight of the Mother) Again if the weight of the Father is F, we have C1 + C2 + F = 52 × 3 = 156 ... (2) Now it is given that the weight of the father = F = 60. By putting this value in equation (2), we have C1 + C2 = 156 - 60 = 96. by using equation (1) we have M = 150 - 96 = 54 kg.