John is a hack author.  He writes a book every 2 months.  He has been writing for 20 years and has earned an average of $30,000 per book.  How much money has he made writing?
He writes 12/2=
<gadget id="calculator">12/2</gadget>
<output>6</output>
6 books a year.
That means he has written 6*20=
<gadget id="calculator">6*20</gadget>
<output>120</output>
120 books.
So he has made 120*30,000=$
<gadget id="calculator">120*30000</gadget>
<output>3_600_000</output>
3,600,000 from writing.

<result>3_600_000</result>