Question

A bus travels a distance of 120 km with a speed of 40 km/her and returns with a speed of 30 km/hr. Calculate the average speed for the entire journey.

Answer 1

Answer:

total distance travelled: 240 km

total Time= 3+4 hr= 7 hr

avg speed= 240/7= 34.28kmph

Answer 2

Answer:

s=120 km

v1 = 40 km/hr

t1= s/v1

= 120/40 = 3 hr

v2 = 30 km/hr

t2 = s/v2

= 120/30 =4 hr

Vav = total distance/total time

= 120+120/4+3

= 240/7

= 34.2 km/hr