James builds a 20 story building.  The first 10 stories are each 12 feet tall each.  The remaining floors are each 3 feet taller.  How tall is the building?
The first 10 floors are 10*12=
<gadget id="calculator">10*12</gadget>
<output>120</output>
120 feet.
There are a remaining 20-10=
<gadget id="calculator">20-10</gadget>
<output>10</output>
10 stories.
They are each 12+3=
<gadget id="calculator">12+3</gadget>
<output>15</output>
15 feet.
So those stories are 15*10=
<gadget id="calculator">15*10</gadget>
<output>150</output>
150 feet.
So the total height is 120+150=
<gadget id="calculator">120+150</gadget>
<output>270</output>
270 feet.

<result>270</result>