Bob buys nose spray.  He buys 10 of them for a "buy one get one free" promotion.  They each cost $3.  How much does he pay?
He got 10/2=
<gadget id="calculator">10/2</gadget>
<output>5</output>
5 paid.
That means he paid 5*3=$
<gadget id="calculator">5*3</gadget>
<output>15</output>
15.

<result>15</result>