In: Statistics and Probability
For each positive integer, n, let P({n}) =(1/2^n)
. Consider the events
A = {n : 1 ≤ n ≤ 10}, B = {n : 1 ≤ n ≤ 20}, and C = {n : 11 ≤ n ≤
20}. Find (a) P(A),
(b) P(B), (c) P(A ∪ B), (d) P(A ∩ B), (e) P(C), and (f) P(B′).
Hint: Use the formula for the sum of a geometric series