Question

How many seconds a caravan 120 metres long running at the rate of 10 m/s will take to pass a standing boy. 

Answer 1

See,
The formula is as follows:
Speed=Distance/time
Take the value which has to be taken out to the L.H.S so the formula becomes:
Time=Distance/Speed
Putting the values we get
Time=120/10
Time=12 seconds
Hope you got your answer! :))

Answer 2

Given,

A caravan 120 metres long is running at the rate of 10 m/s.

To Find,

How many seconds will it take to go by a standing boy?

Solution,

We can solve the question as follows:

It is given that we have to find that in how much time a caravan 120 metres long running at the rate of 10 m/s will take to go by a standing boy.

$Distance = 120\: m$

$Speed = 10\: m/s$

The formula for the time taken by a body to travel a distance at a given speed is:

$Time = \frac{Distance}{Speed}$

Substituting the given values in the above formula,

$Time = \frac{120}{10}$

         $= 12\: seconds$

Hence, the caravan will take 12 seconds.