A local gas station is selling gas for $3.00 a gallon.  An app company is offering $.20 cashback per gallon if you fill up at this station.  If someone buys 10 gallons of gas, how much with their gas be, after the cashback rewards?
Gas is $3.00 a gallon and they buy 10 gallons of gas so that's 3*10 = $
<gadget id="calculator">3*10</gadget>
<output>30</output>
30.00.
The app is offering $0.20 cashback per gallon and they buy 10 gallons so that's .20*10 = $
<gadget id="calculator">0.20*10</gadget>
<output>2</output>
2.00.
They spent $30.00 on gas and their app is offering them $2.00 cashback so they spent 30-2 = $
<gadget id="calculator">30-2</gadget>
<output>28</output>
28.00 per gallon.

<result>28</result>