Question
The ratio of Meera’s father’s age to her mother’s
age is H:K. If the father becomes 7 years older and the mother becomes 3 years younger, the ratio turns 11/7. If the sum of their present ages is 68 years, find Meera’s father’s current age.Solution
ATQ, Father’s age = x Mother’s age = y x + y = 68 — (1) (x + 7) / (y − 3) = 11 / 7 7(x + 7) = 11(y − 3) 7x + 49 = 11y − 33 7x − 11y = −82 — (2) Multiply (1) by 11: 11x + 11y = 748 Add with (2): (11x + 11y) + (7x − 11y) = 748 − 82 18x = 666 x = 666 / 18 = 37 Required answer = 37 years
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