Refactoring in Python, Scope Help Please!

import time
import datetime
import random
from matplotlib import pyplot as plt
import numpy as np
timeList = []
questionNumber = []
exit = 0
timeBeginning = time.time()
timeEnd = time.time()
n = 0




def endTime():

    timeEnd = time.time()
    timeLapse = timeEnd - timeBeginning
    timeList.append(int(timeLapse))


def stats():
      totalCorrect = add_quiz() + subtract_quiz() + multiply_quiz() + divide_quiz()
      print("Total Correct: " + str(totalCorrect))
      print("Total Time Per Each Question: " + str(timeList))
      questionNumber = list(range(1,totalCorrect + 1) )
      x = questionNumber
      y = timeList
      print(x)
      print(y)
      plt.plot(x,y, color="red", marker="o", linestyle ='solid')
      plt.title("Time spent Per Question")
      plt.show()





def add_quiz():
  n = 0
  additionAnswers = 0
  while True:
    n += 1
    maxnum = 2 ** n
    num1 = random.randint(1,maxnum)
    num2 = random.randint(1,maxnum)
    print ("{} + {}".format(num1,num2))
    timeBeginning = time.time()
    answer = int(input(""))
    if (answer == num1 + num2):
        timeEnd = time.time()
        timeLapse = timeEnd - timeBeginning
        timeList.append(int(timeLapse))
        additionAnswers += 1
        continue
    else:
      return additionAnswers


def subtract_quiz():
  n = 0
  subtractionAnswers = 0
  while True:
    n += 1
    maxnum = 2 ** n
    num1 = random.randint(1,maxnum)
    num2 = random.randint(1,maxnum)
    print ("{} - {}".format(num1,num2))
    timeBeginning = time.time()
    answer = int(input(""))
    if (answer == num1 - num2):
        timeEnd = time.time()
        timeLapse = timeEnd - timeBeginning
        timeList.append(int(timeLapse))
        subtractionAnswers += 1
        continue
    else:
      return subtractionAnswers


def multiply_quiz():
  n = 0
  multiplicationAnswers = 0
  while True:
    n += 1
    maxnum = 2 ** n
    num1 = random.randint(1,maxnum)
    num2 = random.randint(1,maxnum)
    print ("{} x {}".format(num1,num2))
    timeBeginning = time.time()
    answer = int(input(""))
    if (answer == num1 * num2):
        timeEnd = time.time()
        timeLapse = timeEnd - timeBeginning
        timeList.append(int(timeLapse))
        multiplicationAnswers += 1
        continue
    else:
      return multiplicationAnswers


def divide_quiz():
  n = 0
  divisionAnswers = 0
  while True:
    n += 1
    maxnum = 2 ** n
    num1 = random.randint(1,maxnum)
    num2 = random.randint(1,maxnum)
    print ("{} / {}".format(num1,num2))
    timeBeginning = time.time()
    answer = int(input(""))
    if (answer == num1 // num2):
        timeEnd = time.time()
        timeLapse = timeEnd - timeBeginning
        timeList.append(int(timeLapse))
        divisionAnswers += 1
        continue
    else:
      return divisionAnswers


def graph():
    pass


def take_quiz():
  print("Welcome to Adam's Math Indexing Quiz")
  print("This Quiz will help you evaluate your math skills and speed!")
  print("Remember: NO CALCULATORS/PAPER!")
  print("Remember: Division is to the nearest whole number (i.e. 10 / 3 = 3, 14 / 3 = 4)")
  response = input("Press enter to start")
  if not response:
    stats()
    post()
    graph()




take_quiz()