Tom swims for 2 hours at a speed of 2 miles per hour.  He then runs for half the time at 4 times the speed.  How many miles did he cover?
He swam 2*2=
<gadget id="calculator">2*2</gadget>
<output>4</output>
4 miles.
He ran for 2/2=
<gadget id="calculator">2/2</gadget>
<output>1</output>
1 hour.
His running speed was 2*4=
<gadget id="calculator">2*4</gadget>
<output>8</output>
8 mph.
So he ran 8*1=
<gadget id="calculator">8*1</gadget>
<output>8</output>
8 miles.
So his total distance was 8+4=
<gadget id="calculator">8+4</gadget>
<output>12</output>
12 miles.

<result>12</result>