Python math bot with added average/total function

def intro():
    print("Lets do some coding!")

def doAddSub(command):
    print("lets " + command + " some numbers")
    input1 = input("Number 1> ")
    input2 = input("Number 2> ")
    number1 = int(input1)
    number2 = int(input2)
    if command == "add":
      result = number1 + number2
      operator = " + "
    elif command == "subtract":
      result = number1 - number2
      operator = " - "
    output = str(result)
    print (input1 + operator + input2 + " = " + output)

def doAvgTot(command):
 # Data collection - include running total
        input1 = input( "Enter the number of numbers you would like to " + command + ": ")
        n = int(input1)
        i = 0
        total = 0
        for i in range(n):
            num = input("Enter number " + str(i) +": ")
            total += int(num)

        if command == "average": # Calculate average
            result = total / n
        else:
            result = total

        # Provide results to user
        print ("The average of your numbers is: " + str(result) + ".")
finished = False

while finished==False:
    phrase = input ("Talk to me > ")
    total = 0
    if phrase == "hi" or phrase == "hey" or phrase == "hello":
        print( "hello")
    elif phrase == "whats your name" or phrase == "what's your name":
        print("Marvin")
    elif phrase == "exit" or phrase == "quit":
        exit;
    elif phrase == "quiz":
        while phrase != "exit" and phrase != "quit":
            phrase = input("What is 1 + 3? ")
            if int(phrase) == 4:
                print ("Correct!")
                break
            else:
                print ("Incorrect - please try again!")
    elif phrase == "average" or phrase == "total":
       doAvgTot(phrase)

    elif phrase == "discount":
        discount = int( input("Please enter the percentage discount: "))
        cost = int( input( "Please enter the item(s) cost: "))
        print ("disc: " + str(discount) + " cost: " + str(cost) + " tot: " + str(total))
        total = cost - (float(discount)*float(cost)/100)
        print("Your " + str(discount) + "% discount of " + str(cost) + " is: " + str(total))
    elif phrase == "add" or phrase == "subtract":
        doAddSub(phrase)
    elif phrase == "bye":
        finished = True
    else:
        print( "Sorry, I don't understand " + "'" + phrase +"'.")

print ("bye")