Jill has a difficult test to study for.  She decides to study one day for 2 hours.  The next day she doubles this amount, and the day after that she studies one hour less than the previous day.  How many minutes does Jill study over the 3 days?
First, we need to determine how many hours Jill studied in total. To find this out, we begin by performing 2*2= 
<gadget id="calculator">2*2</gadget>
<output>4</output>
4 hours spent on day two, double what she spent on day 1.
Next, we perform 4-1= 
<gadget id="calculator">4-1</gadget>
<output>3</output>
3 hours to determine the amount she studied on the third day.
We then add 2+4+3= 
<gadget id="calculator">2+4+3</gadget>
<output>9</output>
9 hours spent in total across 3 days.
Since there are 60 minutes in an hour, she studied 9*60=
<gadget id="calculator">9*60</gadget>
<output>540</output>
540 minutes in total.

<result>540</result>