Membership selection. A town council has 1111 members, 55 Democrats and 66 Repub
ID: 3148282 • Letter: M
Question
Membership selection. A town council has
1111
members,
55
Democrats and
66
Republicans.
(A)
If the president and vice-president are selected at random, what is the probability that they are both Democrats?
(B)
If a 3-person committee is selected at random, what is the probability that Republicans make up the majority?
(A) The probability that they are both Democrats is approximately
. 2727.2727 .
(Type a decimal. Round to three decimal places
(A)
If the president and vice-president are selected at random, what is the probability that they are both Democrats?
Explanation / Answer
total members = 121
Democrats = 55 ; Pr(Democrats) = 5/11
republicans = 66 ; Pr(Republicans) = 6/11
(A) Here Pr(Presiden nd vice president both are democratic) = 5/11 * 5/11 = 25/121 = 0.210
(B) Republicans make up the majority = 3C2 (6/11)2 (5/11) + 3C3 (6/11)3 = 0.568