John invests in a bank and gets 10% simple interest.  He invests $1000.  How much money does he have after 3 years?
He gets 1000*.1=$
<gadget id="calculator">1000*.1</gadget>
<output>100</output>
100 a year.
So after 3 years, he gets 100*3=$
<gadget id="calculator">100*3</gadget>
<output>300</output>
300.
So he has 300+1000=$
<gadget id="calculator">300+1000</gadget>
<output>1_300</output>
1300.

<result>1_300</result>