Question

a train covers the first 16 km at a speed of 20 km per hour another 20 km at 40 km per hour and the last 10 km at 15 km per hour. find the average speed for the entire journey.

Answer 1

at first speed was 20 km per hour

then it became 40 kilometre per hour

then it becomes 15 kilometre per hour average = sum of observations /number of observations

= 20 + 40 + 15 / 3

=75/3

=25

therefore the average speed is 25 kilometre per hour . ANS