Python Puzzles
You have two dice; one is fair and the other unfair. The unfair dice rolls a 6 50% of the time.
What is the probability of choosing the unfair dice if you randomly choose a dice and roll a 6?
You can use Bayes theorem to provide a mathematical proof.
- The probability of the dice being unfair is 75%.
- The probability of the dice being fair is 25%.
import random
unfair_dice = 0
fair_dice = 0
list = []
for _ in range(10_000):
#randomly chooses a dice, 1 or 2
dice = random.randrange(1,3);
#dice 1 is unfair
if dice == 1:
#Probability of rolling a 6 is 50%
diceroll = random.randrange(5,7)
if diceroll == 6: list.append(dice)
#dice 2 is fair
if dice == 2:
diceroll = random.randrange(1,7)
#print(diceroll)
if diceroll == 6: list.append(dice)
#determine percentages
for x in list:
if x == 1:
unfair_dice = unfair_dice + 1
else:
fair_dice = fair_dice + 1
print('The probability of the dice being fair is ' + '{0:.1%}'.format(fair_dice/len(list)))
print('The probability of the dice being unfair is ' + '{0:.1%}'.format(unfair_dice/len(list)))