At Ken's local store, a pound of steak is going for $7. He decides to get two pounds. At the till, he pays using a $20 bill. How much money will he get back?
2 pounds of steak will cost Ken 2 * 7 = 
<gadget id="calculator">2*7</gadget>
<output>14</output>
14 dollars.
Subtracting that amount from $20 will give 20 - 14 = 
<gadget id="calculator">20-14</gadget>
<output>6</output>
6 dollars.
Ken will therefore get 6 dollars back.

<result>6</result>