Kata 8/22 Fizz Buzz

class FizzBuzz
  def self.fizz(num)
    case
      when num % 15 == 0
        "FizzBuzz"
      when num % 3 == 0
        "Fizz"
      when num % 5 == 0
        "Buzz"
      else
        num.to_s
    end
  end
end