Question

A train covers the first half of the distance between two station at a speed of 10 m/sec and the other half at 40 m/sec. Then its average speed for the journey is :

Answer 1

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \huge \mathfrak{ \red{ \underline{Solution}}} \:$

$\large \bold{ \color{blue}{Average \: speed \: = \frac{total \: distance}{total \: time} }}$

• Let 2s be total distance

• $total \: time \: = \: \frac{s}{40} + \frac{s}{60} = \frac{s}{24}$

Therefore

• Average speed = $\frac{2s}{ \frac{s}{24} }$

• 48 km /hr

Hence,

The average speed of whole journey is 48 km/hr