A train travel 20km at a uniform speed 60km/1hr and the next 20km at a uniform speed of 80km/1hr calculate its average speed

Answer 1

avgspeed=distance/time

time= 20/60 + 20/80 hrs=1/3 + 1/4 hr
= 7/12 hr

distance=40 km

Answer 2

126

Answer 3

68 . 57

Answer 4

yes 68.57 is correct but i want the solution also