Question
Two years ago, the age ratio of 'D' and 'E' was 7:9. In ten
years from now, their age ratio will be 9:11. Find the present age of 'K', who is 3 years younger than 'E'.Solution
ATQ,
Let the age of 'D' and 'E', two years ago be '7a' and '9a' years, respectively.
So, (7a + 2 + 10) : (9a + 2 + 10) = 9 : 11
Or, 11 × (7a + 12) = 9 × (9a + 12)
Or, 77a + 132 = 81a + 108
Or, 4a = 24
So, a = 6
Required age = 9 × 6 + 2 - 3 = 53 years
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