Mark has 12 candy bars in total between Mars bars, Snickers, and Butterfingers.  He has 3 Snickers and 2 Mars bars.  How many Butterfingers does he have?
Not counting Butterfingers Mark has 3+2=
<gadget id="calculator">3+2</gadget>
<output>5</output>
5 candy bars.
So Mark has 12-5=
<gadget id="calculator">12-5</gadget>
<output>7</output>
7 Butterfingers.

<result>7</result>