There are 4 alligators living on a golf course in Florida. If the number of alligators doubles every six months, how many alligators will there be at the end of a year?
First figure out how many times the alligator population doubles in one year by dividing the number of months in a year by the number of months it takes the population to double: 12 months / 6 months = 
<gadget id="calculator">12/6</gadget>
<output>2</output>
2. The alligator population doubles twice.
Now double the alligator population once: 4 alligators * 2 = 
<gadget id="calculator">4*2</gadget>
<output>8</output>
8 alligators.
Now double it again: 8 alligators * 2 = 
<gadget id="calculator">8*2</gadget>
<output>16</output>
16 alligators.

<result>16</result>