Skidoo racing is a popular sport in many countries. It takes about 5 minutes to travel $8km$ along the track. 
We can use this information to calculate the skidoo's speed. Take care! We need to work in the correct units - metres and seconds.
distance travelled $ = 8km = 8000m$
time taken $ = 5\min utes = 300s$
$speed = \frac{{distance}}{{time}} = \frac{{8000m}}{{300s}} = 26.7m/s$

How far?

The faster you run and the longer you run for, the farther you will get. You can work out how far using the equation for speed.
The equation must be rearranged like this:
distance travelled = average speed x time taken
Or simply:
distance = speed x time
Here is an example:
A bus is travelling along a road. Its speed is $25m/s$.
How far will it travel in one minute ($60s$)?
distance travelled = speed x time taken
                             $\eqalign{
  &  = 25m/s \times 60s  \cr 
  &  = 1500m \cr} $
So the bus will travel $1500m\,(1/5km)$ in one minute.

How long?

You can also use the equation for speed to calculate the time a moving object's journey will take.
The equation must be rearranged like this:
$\begin{array}{l}
\begin{array}{*{20}{c}}
{time}&{taken}
\end{array} = \frac{{\begin{array}{*{20}{c}}
{distan ce}&{travelled}
\end{array}}}{{\begin{array}{*{20}{c}}
{average}&{speed}
\end{array}}}\\
\begin{array}{*{20}{c}}
{Or}&{simply}
\end{array}:\\
time = \frac{{distance}}{{speed}}
\end{array}$

Here is an example:
An aircraft flies at an average speed of $250m/s$.
How long will it take to fly between two airports $750km$ apart?
$\begin{array}{*{20}{c}}
{time}&{taken}
\end{array} = \frac{{\begin{array}{*{20}{c}}
{distance}&{travelled}
\end{array}}}{{\begin{array}{*{20}{c}}
{average}&{speed}
\end{array}}} = \frac{{750000m}}{{250m/s}} = 3000s$
So the aircraft will take 3000s, which is 50 minutes