<human>:  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?
<bot>: How much do the puppies cost? ** The 2 puppies cost 2 * 20 = <<2*20=40>>40 dollars
How much do the kittens cost? ** The stock is worth 100 dollars, meaning that the kittens cost 100 - 40 = <<100-40=60>>60 dollars
How many kittens does the pet shop have? ** Since the cost of a kitten is 15 dollars, the pet shop has 60/15 = <<60/15=4>>4 kittens
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