One week is 7 days, so for one week, Mike trained for 7 * 2 = <<7*2=14>>14 hours.
The second week he began to train for 3 hours a day, so he trained for 7 * 3 = <<7*3=21>>21 hours.
That means Mike in total trained for 21 + 14 = <<21+14=35>>35 hours.
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