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One man speaking to other:

When you were born I was 20 years old. Today I am twice the age you were when I was the age you are now.

What are the ages of both of them?

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up vote 4 down vote accepted

80 and 60

I think it's helpful to break up and reword the problem: "I am 20 years older than you." "When I was your current age, you were (of course) 20 years younger than me." "I am now twice the age you were at that time."

And I don't really know how I got from that, to 80. But it works:

Man A is 20 years older than man B. When man A is 80, man B is 60. When man A was 60, man B was 40. "When I was your current age (60), you were 20 years younger than me (40)." "I am now twice the age you were at that time (80)."

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The way to get there is x-20 = y and x = 2 * (y-20) – Luis Oct 3 '12 at 3:20

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