Question
The present age of Surjeet and Rakesh are in the ratio
of 4:5. After 8 years the ratio of their ages will be 6:7. What is 70% of the sum of their present ages?Solution
Let the present ages of Surjeet and Rakesh be 4x and 5x respectively Thus, (4x + 8)/(5x + 8 ) = 6/7 28 x + 56 = 30 x + 48 30 x - 28 x = 56 – 48 2 x = 8 x = 4 Sum of their ages = 4 x + 5 x = 9 x = 9 × 4 = 36 years ∴ 70% of 36 = 70/100 × 36 = 25.2 years
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