A technician makes a round-trip to and from a certain service center by the same route. If the technician completes the drive to the center and then completes 40 percent of the drive from the center, what percent of the round-trip has the technician completed?
Choose the correct choice from the following.
A) 30
B) 40
C) 70
D) 80
E) 60
round trip means 2 trips i.e.to and fro. He has completed one i.e 50% completed. then he traveled another 40% of 50% i.e 20%. so he completed   50 +20= 
<gadget id="calculator">  50 +20</gadget>
<output>70</output>
70 % of total trip   70
<result>C</result>
A technician makes a round-trip to and from a certain service center by the same route. If the technician completes the drive to the center and then completes 40 percent of the drive from the center, what percent of the round-trip has the technician completed?