The sum of the present ages of A, B, C is 51 years. Three years ago their ages were in the ratio 1:2:3. What is the present age of A?	Choose the correct choice:
A) 7  B) 8  C) 9  D) 10  E) 11
Three years ago:   a:b:c = 1:2:3   Let a = 1x, b = 2x, and c = 3x.   Today:   (x+3) + (2x+3) + (3x+3) = 51   x = 7   So the present age of A is x+3 = 10   The answer is 10.
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The sum of the present ages of A, B, C is 51 years. Three years ago their ages were in the ratio 1:2:3. What is the present age of A?