SOLUTION: consider the random variable X to be number of heads obtained on 3 flips of a fair coin. Write out the probability mass function and the probability distribution function for X.

Algebra ->  Probability-and-statistics -> SOLUTION: consider the random variable X to be number of heads obtained on 3 flips of a fair coin. Write out the probability mass function and the probability distribution function for X.       Log On


   

Question 1050387: consider the random variable X to be number of heads obtained on 3 flips of a fair coin.
Write out the probability mass function and the probability distribution function for X.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
There are eight possible outcomes
HHH-3
HHT-2
HTH-2
HTT-1
THH-2
THT-1
TTH-1
TTT-0
So then,
PMF%280%29=1%2F8
PMF%281%29=3%2F8
PMF%282%29=3%2F8
PMF%283%29=1%2F8
The cumulative distribution function is then,
CDF%280%29=1%2F8
CDF%281%29=1%2F8%2B3%2F8=1%2F2
CDF%282%29=1%2F2%2B3%2F8=7%2F8
CDF%283%29=1