John has a large water collection tank.  The tank can hold 200 gallons.  It weighs 80 pounds empty.  A rainstorm fills it to 80% of capacity.  If a gallon of water weighs 8 pounds, how much does it weigh now?
The tank has 200*.8=
<gadget id="calculator">200*.8</gadget>
<output>160</output>
160 gallons of water in it.
That water weighs 160*8=
<gadget id="calculator">160*8</gadget>
<output>1_280</output>
1280 pounds.
So in total it weighs 1280+80=
<gadget id="calculator">1280+80</gadget>
<output>1_360</output>
1360 pounds.

<result>1_360</result>