Two vampires have come to the sleepy village of Willowton, population 300. Every night, each vampire turns 5 more people into vampires. How many vampires are there after two nights?
First find the number of new vampires after one night: 5 people/vampire * 2 vampires = 
<gadget id="calculator">5*2</gadget>
<output>10</output>
10 people.
Add that to the starting number of vampires to find the total number of vampires after one night: 10 vampires + 2 vampires = 
<gadget id="calculator">10+2</gadget>
<output>12</output>
12 vampires.
Then find the number of new vampires on the second night: 5 people/vampire * 12 vampires = 
<gadget id="calculator">5*12</gadget>
<output>60</output>
60 people.
Add that number to the starting number of vampires on the second night to find the total number of vampires after two nights: 60 vampires + 12 vampires = 
<gadget id="calculator">60+12</gadget>
<output>72</output>
72 vampires.

<result>72</result>