Ben bought a car for $20000 in 2007. The price of the car depreciates at a constant rate of 21% per year. Find the price of the car in the year 2010.
The price of the car depreciates of 20000 * 21% = $
<gadget id="calculator">20000*21*.01</gadget>
<output>4_200</output>
4200 per year.
Ben had the car for 2010 - 2007 = 
<gadget id="calculator">2010-2007</gadget>
<output>3</output>
3 years.
The price of the car depreciates 4200 * 3 = $
<gadget id="calculator">4200*3</gadget>
<output>12_600</output>
12600 from 2007 to 2010.
So the price of the car in the year 2010 is $20000 - $12600 = $
<gadget id="calculator">20000-12600</gadget>
<output>7_400</output>
7400.

<result>7_400</result>