Question

A train travels the first 15km at a uniform speed of 50km/h and At the last 10 km at uniform speed of 20km/h. claculate the average speed for the entire journey.​

Answer 1

Answer:

according to me it is incomplete

Answer 2

distance[1]=15km

speed[1]=50km/h

distance[2]=10km

speed[2]=20km/h

time[1]= d[1]/s[1]

          = 15/50= 3/10h

time[2]= 10/20=1/2h

average speed=total distance/total time

                        = 25÷3/10+1/2

                        =25÷8/10

                        = 25×10/8

                        =250/8=31.25km/h