Doing Math with Python Chapter 1 programming challenge

1_1.py

def odd_or_even(x):
    if x % 2 == 0:
        return 'even'
    else:
        return 'odd'


def next_nine_number(x):
    for i in range(0, 9):
        x = x + 2
        yield x


if __name__ == '__main__':
    n = input('Enter a number: ')
    n = float(n)
    if n.is_integer():
        n = int(n)
        print(odd_or_even(n))
        for i in next_nine_number(n):
            print(i)
    else:
        print('Please enter an integer')

1_2.py

def multi_table_2(a, times):
    for i in range(1, times+1):
        print('{0} x {1} = {2}'.format(a, i, a*i))

if __name__ == '__main__':
    a = input('Enter a number: ')
    b = input('How many answers do you want?: ')
    multi_table_2(float(a), int(b))

1_3.py

def print_menu():
    print('1. Kilometers to Miles')
    print('2. Miles to Kilometers')
    print('3. Kilograms to Pounds')
    print('4. Pounds to Kilograms')
    print('5. Celsius to Fahrenheit')
    print('6. Fahrenheit to Celsius')


def km_miles():
    km = float(input('Enter distance in kilometers: '))
    miles = km / 1.609
    print('Distance in miles: {0}'.format(miles))


def miles_km():
    miles = float(input('Enter distance in miles: '))
    km = miles * 1.609
    print('Distance in kilometers: {0}'.format(km))


def kg_pounds():
    kg = float(input('Enter weight in kilograms: '))
    pounds = kg * 2.20462262
    print('Weight in pounds: {0}'.format(pounds))


def pounds_kg():
    pounds = float(input('Enter weight in pounds: '))
    kg = pounds / 2.20462262
    print('Weight in kilograms: {0}'.format(kg))


def celsius_f():
    celsius = float(input('Enter temperature in celsius: '))
    fahrenheit = celsius * (9 / 5) + 32
    print('Temperature in fahrenheit: {0}'.format(fahrenheit))


def fahrenheit_c():
    fahrenheit = float(input('Enter temperature in fahrenheit: '))
    celsius = (fahrenheit - 32) * (5 / 9)
    print('Temperature in celsius: {0}'.format(celsius))


if __name__ == '__main__':
    print_menu()
    choice = input('Which conversion would you like to do? ')

    if choice == '1':
        km_miles()
    if choice == '2':
        miles_km()
    if choice == '3':
        kg_pounds()
    if choice == '4':
        pounds_kg()
    if choice == '5':
        celsius_f()
    if choice == '6':
        fahrenheit_c()