John buys 3 dress shirts.  They sell for $20 each.  He also has to pay 10% tax on everything.  How much did he pay in total?
The shirts cost 3*$20=$
<gadget id="calculator">3*20</gadget>
<output>60</output>
60 before tax.
The tax cost $60*.1=$
<gadget id="calculator">60*.1</gadget>
<output>6</output>
6.
So in total they paid $60+$6=$
<gadget id="calculator">60+6</gadget>
<output>66</output>
66.

<result>66</result>