Question
The average age of three children in a family is 25% of
the average of the age of father and the eldest child. The total age of the mother and the younger child is 49 years. If the father’s age is 28 years, what is the age of the second child?Solution
Given that the average age of three children in the family is 25% of the average of the father and the eldest child Therefore, let us suppose the age of the three children be a, b , c And the average would be = (a+b+c)/3 = 25/100×(28+c)/2 = (a+b+c)/3 = (28+c)/8……………..(i) Let us suppose that the age of mother is d, ∴ d + a = 49 …………………(ii) Even from both the equations, value of b cannot be determined.
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