Probability Simulation in Python

Question

I was given a probability problem, and I wrote a script to test it.

Two unbiased dice are thrown once and the total score is observe. Find de probabiity that: a) The total score is even or greater than 7

I wrote the following script in Python, and it should give me the probability of "A" correct.

import random

def thing(trials):

    i = 0
    number = 0

    while i < trials:

        answer1 = random.choice([1, 2, 3, 4, 5, 6])
        answer2 = random.choice([1, 2, 3, 4, 5, 6])


        if (answer1 + answer2)%2 == 0:
            number += 1.0
        elif (answer1 + answer2) > 7:
            number += 1.0

        i += 1

    print number/i

This gives me 2/3 as the answer, which is correct. Thanks!

BrenBarn BrenBarn · Accepted Answer · 2012-07-06T05:10:22

By my calculations 10/12 is correct. @Thrustmaster listed the possibilites, but without their probability of occurrence. Taking probability of occurrence into account there are 30 desirable outcomes, out of 36 possible rolls, which is 5/6 (or 10/12 as you have it).

Edit: I see you updated your question to change the problem. In this case, yes, 2/3 is correct.

Probability Simulation in Python

2 Answers