A storm dropped 5 inches of rain in the first thirty minutes.  In the next 30 minutes, the hurricane dropped half that amount of rain.  It then dropped 1/2 inch of rain for the next hour.  What was the average rainfall total for the duration of the storm?
The storm dropped 5 inches then half that amount so 5/2 = 
<gadget id="calculator">5/2</gadget>
<output>5/2 = around 2.5</output>
2.5 inches.
The next hour the storm dropped 1/2 inch of rain for 1 hour so 1*.5 = 
<gadget id="calculator">1*.5</gadget>
<output>0.5</output>
.5 inches.
All total the storm dropped 5 inches + 2.5 inches + .5 inch for = 
<gadget id="calculator">5+2.5+.5</gadget>
<output>8</output>
8 inches.
It rained for 2 hours total so 8/2 = 
<gadget id="calculator">8/2</gadget>
<output>4</output>
4 inches of rain per hour.

<result>4</result>