Question 1062527: In 10 years A will be twice as old as B was 10 years ago. If A is now 9 years older than B then the present age of B is? Answer by ikleyn(52781) (Show Source):
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In 10 years A will be twice as old as B was 10 years ago. If A is now 9 years older than B then the present age of B is?
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The condition says:
A + 10 = 2*(B-10), (1) ("In 10 years A will be twice as old as B was 10 years ago.")
A = B + 9. (2) (" A is now 9 years older than B:)
From (2), substitute the expression A = B + 9 into (1), replacing A. You will get
(B+9) + 10 = 2(B-10),
B + 19 = 2B - 20 ---> 19 + 20 = B.
Hence, B is 39 years old now.
Then A = B + 9 = 39 + 9 = 48 years old now.
