Max was doing homework in three different subjects. It took him 20 minutes to finish tasks from biology and two times more time to finish history. Geography took him the most time, three times more than history. How much time did Max spend on doing his homework?
How long did it take Max to finish history? ** Max finished history in 20 * 2 = <<20*2=40>>40 minutes.
How long did it take Max to finish geography? ** Finishing geography took the most time, which is 40 * 3 = <<40*3=120>>120 minutes.
How much time did Max spend on doing his homework? ** In total, for all three subjects, Max needed 20 + 40 + 120 = <<20+40+120=180>>180 minutes.
#### 180