input: from typing import List
  
  
  def recursive_problem_solving(problem: List[float]) -> List[float]:
      """ Use recursion to solve a given problem in Python. The problem is defined as
      a list of numbers that need to be transformed by removing the middle number and
      repeating this process until only one number remains.
      >>> recursive_problem_solving([1.0, 2.0, 3.0, 4.0])
      [1.0]
      >>> recursive_problem_solving([5.0, 6.0, 7.0, 8.0, 9.0])
      [5.0]
      """
output:     if len(problem) == 1:
          return problem
      mid_index = len(problem) // 2
      new_problem = problem[:mid_index] + problem[mid_index+1:]
      return recursive_problem_solving(new_problem)