Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • School
  • A train travels somedistances with a speed of 30 km/hr and return with a speed of 45 km /hr . calculate the average speed of the train​

A train travels somedistances with a speed of 30 km/hr and return with a speed of 45 km /hr . calculate the average speed of the train​

Answers (1)

best_answer

\\ Let \ a \ distance \ x \ k m$ be travelled with a speed of $30 km / h$ \\ \\ Time taken $, t_{1}=\frac{x}{30} h,$ On return journey, $t_{2}=\frac{x}{45} h$ \\ \\ Total time, $t=t_{1}+t_{2}=\frac{x}{30}+\frac{x}{45}=x\left[\frac{1}{30}+\frac{1}{45}\right]$ \\ \\ $t=x \frac{(3+2)}{90}=\frac{x}{18}$ \\ \\ Total distance $=x+x=2 x$ \\ \\ Average speed $=\frac{\text { total distance }}{\text { total time }},=\frac{2 x}{x / 18}=36 km / h$

Posted by

Deependra Verma

View full answer

Similar Questions

Latest Question