At a convention, 16 of 36 delegates arrived with pre-printed name badges. Half of the remaining delegates made their own, hand-written name badges. How many delegates were not wearing name badges?
There were 36-16=
<gadget id="calculator">36-16</gadget>
<output>20</output>
20 without pre-printed name badges.
Then 20/2=
<gadget id="calculator">20/2</gadget>
<output>10</output>
10 made hand-written badges.
There were 20-10=
<gadget id="calculator">20-10</gadget>
<output>10</output>
10 with no name badge.

<result>10</result>