Calculator for binomial distributions

binomial_calculator.py

# By Jim Heald

import math

while True:
    answer = 0
    n = float(input('n: '))
    p = float(input('p: '))
    st = int(input('start: '))
    end = int(input('end: '))
    for x in range(st, end+1):
        answer += (math.factorial(n)/(math.factorial(x) * math.factorial(n-x))) * p**x * (1-p)**(n-x)
    print(answer)
    input("Again? ")
    continue