City A to city B, John drove for 1 hour at 40 mph and for 3 hours at 60 mph. What was the average speed for the whole trip?  Choose the correct choice from the following.
A) 57 B) 57.5 C) 58.2 D) 59 E) 55
The total distance is 1×40+3×60=220   And the total time is 4 hours.   Hence,   Average Speed=(Total Distance/Total Time)=220/4= 
<gadget id="calculator">220/4</gadget>
<output>55</output>
55   Answer : 55
<result>E</result>
City A to city B, John drove for 1 hour at 40 mph and for 3 hours at 60 mph. What was the average speed for the whole trip?