Question
The ratio of the present ages of A and B is 10:7. After
8 years, the ratio of their ages will be 12:9. Find the ratio of their ages 12 years ago.Solution
Let the present ages of A and B be 10x and 7x years, respectively
(10x + 8) / (7x + 8) = 12 / 9
Or, 90x + 72 = 84x + 96
Or, 6x = 24
Or, x = 4
Required ratio = (10x – 12) / (7x – 12) = (40 – 12) : (28 – 12) = 28 : 16 = 7 : 4
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