Question 605370
Add up the times:


  2 hrs  20 min
+ 1 hr   45 min
----------------
  3 hrs  65 min


But 65 min = 1 hr 5 min, so we carry that extra hour over and add it to the 3 hrs already there. 


This means that the answer is <font color="red">4 hrs 5 min</font>