A pet shop has 2 puppies and some kittens. A puppy costs $20, and a kitten costs $15. If the stock is worth $100, how many kittens does the pet shop have?
The 2 puppies cost 2 * 20 = 
<gadget id="calculator">2*20</gadget>
<output>40</output>
40 dollars.
The stock is worth 100 dollars, meaning that the kittens cost 100 - 40 = 
<gadget id="calculator">100-40</gadget>
<output>60</output>
60 dollars.
Since the cost of a kitten is 15 dollars, the pet shop has 60/15 = 
<gadget id="calculator">60/15</gadget>
<output>4</output>
4 kittens.

<result>4</result>