It is given in the question that
At a warehouse the employees can unload 18 trucks in 6 hours.
And we have to find the unit rate for unloading trucks .
Unit rate means , number of trucks unloaded per hour. And to find it, we have to divide number of trucks by number of hours. That is
[tex]= \frac{18}{6} = 3 trucks \ per \ hour[/tex]
Therefore the unit rate is 3 trucks per hour .
