Question 1029730
Let B: Betty's age (today)
       M: Mike's age (today).

We have the equations: 

1) B= 3×M
2)(B +5) = 2×(M+5) 

So 1) in 2) 3×M + 5 = 2×M + 10

             M = 5.

ANSWER: Mike is 5 years-old ( Betty is 15 years-old).

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