Question
The present ages of A and B are in the ratio 7 : 5.
After 6 years, the ratio of their ages will be 4 : 3. Find A's present age.Solution
Let present ages be 7x and 5x. After 6 years: (7x + 6) / (5x + 6) = 4 / 3 3(7x + 6) = 4(5x + 6) 21x + 18 = 20x + 24 21x − 20x = 24 − 18 x = 6 So, A’s age = 7x = 42 years B’s age = 5x = 30 years Answer: A = 42 years
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