Question
4 years ago, ratio of ages of A and B was 3:4. 4 years
hence, ratio will be 4:5. Find B's present age.Solution
ATQ, Gap between "4 years ago" and "4 years hence" = 8 years. Ratio gap (3 to 4) = 1 unit. 1 unit = 8 years. B's age (4 yrs ago) = 4 units = 32. Present = 32 + 4 = 36.
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