Question
My grandfather’s age was seven times older to me
14 years ago. He would be two times of my age seven years from now. Seven years ago, what was the ratio of the age to that of my grandfather?Solution
Let my age 14 years ago be x years My grandfather’s age at that time = 7x years My present age = (x+ 14) years My grandfather’s present age = (7x+ 14) years 2(x+ 14 + 7) = (7x + 14 + 7) 2x + 42 = 7x + 21 5x = 21 x = 21/5 Seven years ago, ratio of ages => (x+14-7)/(7x+14-7) = (x+7)/(7x+7) => (21/5+7)/(7 × 21/5+7) = (56/5)/(182/5) = 56: 182 => 4:13
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