Question
Average of present ages of A and B is 30 years. Ratio of
age of A to age of B, after 10 years will be 7:9, respectively. What will be the ratio of their ages 16 years ago?Solution
Let, present age of A is ‘x’ years Present age of B = 30 × 2 – x = ‘60 – x’ years According to question; (x + 10)/(60 – x + 10) = 7/9 Or, 9x + 90 = 490 – 7x Or, 16x = 400 Or, x = 25 Desired ratio = (25 – 16):(60 – 25 – 16) = 9:19
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