Tom decides to take 10 dance lessons that cost $10 each, but he gets two of them for free. How much does he pay?
He paid for 10 - 2 = 
<gadget id="calculator">10-2</gadget>
<output>8</output>
8 lessons.
That means he pays 8 * $10 = $
<gadget id="calculator">8*10</gadget>
<output>80</output>
80.

<result>80</result>