James buys steaks for buy one get one free.  The price is $15 per pound and he buys 20 pounds.  How much did he pay for the steaks?
He pays for 20/2=
<gadget id="calculator">20/2</gadget>
<output>10</output>
10 pounds of steaks.
That cost 10*15=$
<gadget id="calculator">10*15</gadget>
<output>150</output>
150.

<result>150</result>