Mark collects money for the homeless.  He visits 20 households a day for 5 days and half of those households give him a pair of 20s.  How much did he collect?
He got money from 20/2=
<gadget id="calculator">20/2</gadget>
<output>10</output>
10 households per day.
So that means he got money from 10*5=
<gadget id="calculator">10*5</gadget>
<output>50</output>
50 households.
Each of those houses gave 20*2=$
<gadget id="calculator">20*2</gadget>
<output>40</output>
40.
So he raised 40*50=$
<gadget id="calculator">40*50</gadget>
<output>2_000</output>
2000.

<result>2_000</result>