Question

Find the average speed of an auto rickshaw that covers a distance of 380 km in 10 hours after stopping in between for 2 hours.

Answer 1

Hint: First, before proceeding for this, we must know the following relationship between the time , speed and distance to get the desired result. Then, the relationship between time(t), speed(s) and distance(d) is $s=\dfrac{d}{t}$. Then, one more condition is mentioned in the question that the auto rickshaw stopped for 2 hours. So, by substituting the value of the distance d and time t, we get our average speed.

Complete step-by-step answer:
In this question, we are supposed to find the average speed of the auto rickshaw.
So, before proceeding for this, we must know the following relationship between the time , speed and distance to get the desired result.
Now, the relationship between time(t), speed(s) and distance(d) is:
$s=\dfrac{d}{t}$
So, to get the average speed of the auto rickshaw, we can substitute the values of the distance as 380 km and time taken for the travel as 10 hours.
Here, one more condition is mentioned in the question that the auto rickshaw stooped for 2 hours.
So, now the total time taken to complete the journey will become as:
10+2=12 hours
So, now by substituting the value of the distance d=380km and time t=12 hours, we get:
$s=\dfrac{380}{12}$
Then, by solving the above expression we get the average speed as:
$s=\dfrac{95}{3}km/hr$
So, the average speed of an auto rickshaw that covers a distance of 380 km in 10 hours after stopping in between for 2 hours is $\dfrac{95}{3}km/hr$.
Hence, we get the average speed as $\dfrac{95}{3}km/hr$.

Note: The only mistake in these type of questions we may occur is to forget about the condition given in the question that the auto rickshaw takes a pause of 2 hours in between and we calculate without considering it so then we get the answer as:
$\begin{align}
  & s=\dfrac{380}{10} \\
 & \Rightarrow s=38 \\
\end{align}$
Then, we get the average speed as 38km/hr which is an incorrect answer.