Question
Find the probability distribution of X, the number of heads, in the two tosses of a coin (or a simultaneous toss of two coins).
Solution
Here X can take the values 0, 1 or 2.
= P(tails on first loss and tails on the second toss)
= P(tails on first toss) x P(tails on second toss)
P(X = 1) = P(1 head) = P(HT or TH)
= P(HT) + P(TH)
P(X = 2) = P(2 heads) = P(HH) =
= P(tails on first loss and tails on the second toss)
= P(tails on first toss) x P(tails on second toss)
P(X = 1) = P(1 head) = P(HT or TH)
= P(HT) + P(TH)
P(X = 2) = P(2 heads) = P(HH) =
