July 8th, 2019, 05:55 AM  #1 
Newbie Joined: Jun 2019 From: Melbourne Posts: 4 Thanks: 0  Probability
If a man has 15 balls in his left pocket and 12 balls in his right pocket and repeatedly grabs either box at random to take a ball out, what is the probability that he gets to a point where he has 10 balls in each pocket?

July 8th, 2019, 01:54 PM  #2 
Global Moderator Joined: May 2007 Posts: 6,786 Thanks: 708 
Assuming each pocket equally likely to be chosen, the question becomes: after choosing 7 balls, what is the probability that he has chosen 5 balls from the left and 2 balls from the right. The answer is the binomial term $\frac{1}{2^7}\binom{7}{5}=0.1640625$.


Tags 
prob or math, probability 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
The probability of this being another probability question  Devans99  Probability and Statistics  4  June 25th, 2018 01:06 PM 
Continuous probability; find probability density function  rivaaa  Advanced Statistics  5  November 5th, 2015 01:51 PM 
probability set theory  probability of x out of n events  hbonstrom  Applied Math  0  November 17th, 2012 07:11 PM 
Joint probability density function, probability  token22  Advanced Statistics  2  April 26th, 2012 03:28 PM 
Probability (probability mass function,pmf)  naspek  Calculus  1  December 15th, 2009 01:18 PM 