Question
The ratio of age of A and B after 8 years is 4:5
respectively. The ratio of age of A and C 6 years ago is 3:4 respectively. If the present average age of A and C is 30 years, then find the present age of C.Solution
Let the age of A and B after 8 years be 4x years. and 5x years respectively. And the present age of C is ‘y’ years. So, (4x – 14)/ (y – 6) = 3/4 16x – 56 = 3y – 18 16x – 3y = 38……………. (1) And 4x – 8 + y = 60 y = 68 – 4x…………………. (2) From equations (1) and (2), we get. 16x – 204 + 12x = 38 28x = 242 x = 8.6 Present age of C = 62 -(4 ×8.6) = 27.6years
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