Let W be a random variable giving the number of heads minus the
number of tails in three tosses of a coin. (i) List the elements of the
sample space S for the three tosses of the coin and to each sample
point assign a value w for W. (ii) Find the probability distribution of
the random variable W assuming that the coin is biased so that a
head is twice as likely to occur as a tail

Question

Let W be a random variable giving the number of heads minus the 
number of tails in three tosses of a coin. (i) List the elements of the 
sample space S for the three tosses of the coin and to each sample 
point assign a value w for W. (ii) Find the probability distribution of 
the random variable W  assuming that the coin is biased so that a 
head is twice as likely to occur as a tail