Question 158650
First, let's convert the denominator of "hour" to "seconds":
72 miles     1 hour   1 min
--------- x  ------ x ------  
 hour        60 min   60 sec
.
Note: notice how the like-units cancel leaving:
72 miles
---------
36 sec
.
Now, let's convert the numerator of "miles" to "meters":
72 mile     5280 ft     
-------- x --------- x ------------
36 sec      1 mile      1 ft
.
Again, notice how the units cancel leaving:
(72*5280*0.3048) meters0.3048 meter
-----------------------
        36 sec
Resulting in:
115872.768 meters
------------------
     36 sec
Finally, we get:
3218.688 meters/sec