A trained covered x km at 40 kmph and another 2x km at 20 kmph. Find the average speed of the train in covering the entire 7x km. Choose the correct choice from the following answers:
A) 56
B) 18
C) 24
D) 19
E) 12
Total time taken = x/40 + 2x/20 hours   = 5x/40 = x/8 hours   56verage speed = 7x/(x/8) = 56 kmph   56nswer: 56
<result>A</result>
A trained covered x km at 40 kmph and another 2x km at 20 kmph. Find the average speed of the train in covering the entire 7x km.