In a house, there are 16 cats. Two of them are white, and 25% of them are black. The rest of the cats are grey. How many grey cats are in this house?
In this house, there are 16 * 25/100 = 
<gadget id="calculator">16*25/100</gadget>
<output>4</output>
4 black cats.
If there are two white cats, that means that there are 16 - 4 - 2 = 
<gadget id="calculator">16-4-2</gadget>
<output>10</output>
10 grey cats in this house.

<result>10</result>