If three unbiased coins are tossed, find the probability that they are all heads
-
A.
(frac{1}{2}) -
B.
(frac{1}{3}) -
C.
(frac{1}{9}) -
D.
(frac{1}{8})
Correct Answer: Option D
Explanation
P(H) = (frac{1}{2}) and P(T) = (frac{1}{2})
Using the binomial prob. distribution,
(H + T)3 = H3 + 3H2T1 + 3HT2 + T3
Hence the probability that three heads show in a toss of the three coins is H3
= ((frac{1}{2}))3
= (frac{1}{8})