#!/usr/bin/env python2

 import subprocess
 import random
 import argparse
 
 p = argparse.ArgumentParser()
 p.add_argument('probability', nargs=2)
 p.add_argument('program')
 
 args = p.parse_args()
 
 prob = map(float, args.probability)
 prob = prob[0]/prob[1]
 
 if random.random() < prob:
     subprocess.call(args.program)