Question
Ratio of present ages of mother and her son is 21:10
respectively. Father’s present age is 17 years more than that of mother. If the present average age of mother, father, and son is 39 years, then find the ratio of present ages of mother and father respectively.Solution
ATQ, Let present ages of mother and son be ‘21x’ years and ‘10x’ years respectively. So, present age of father = (21x + 17) years So, 21x + 10x + 21x + 17 = 39 × 3 = 117 Or, 52x = 100 Or, x = 2 Present age of mother = 21 × 2 = 42 years Present age of father = 42 + 17 = 59 years Desired ratio = 42:59 = 6:7
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