Tom wants to visit Barbados.  He needs to get 10 different vaccines to go and a doctor's visit.  They each cost $45 and the doctor's visit costs $250 but insurance will cover 80% of these medical bills.  The trip itself cost $1200.  How much will he have to pay?
The medical cost comes out to 45*10+250=$
<gadget id="calculator">45*10+250</gadget>
<output>700</output>
700.
Insurance covers 700*.8=$
<gadget id="calculator">700*.8</gadget>
<output>560</output>
560.
So he has to pay 700-560=$
<gadget id="calculator">700-560</gadget>
<output>140</output>
140.
Added to the cost of the trip he has to pay 1200+140=$
<gadget id="calculator">1200+140</gadget>
<output>1_340</output>
1340.

<result>1_340</result>