Question
The ratio of age of Karan 9 years ago to the age of
Pooja 9 years hence is 4:6. If the average of their present ages is 38 years, what is the difference between their present ages?Solution
ATQ Let the present age of Karan and Pooja be ‘k’ years and ‘p’ years, respectively. So, (k – 9) / (p + 9) = 4 / 6 Or, 6k – 54 = 4p + 36 Or, 6k – 4p = 90 ------------------ (1) Also, k + p = 2 × 38 = 76--------------- (2) Equation (2) × 4 + Equation (1), we get 10k = 394 Or, k = 39.4 (approximately 39) So, p = 76 – 39 = 37 Required difference = 39 – 37 = 2 years
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