SOLUTION: A club with 23 members is voting on a proposal. A group of 5 has decided to vote in favor of the proposal while each of the rest of the members vote independently with a chance of

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Question 859933: A club with 23 members is voting on a proposal. A group of 5 has decided to vote in favor of the proposal while each of the rest of the members vote independently with a chance of 50% in favor of the proposal. What are the chances that the proposal will get the majority vote.
Found 2 solutions by stanbon, ewatrrr:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A club with 23 members is voting on a proposal. A group of 5 has decided to vote in favor of the proposal while each of the rest of the members vote independently with a chance of 50% in favor of the proposal. What are the chances that the proposal will get the majority vote.
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Majority means >= 12
5 are already in favor.
Need >= 7 out of 12.
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P(x >= 7) = 1 - P(x<=6) = 1-binomcdf(12,0.5,6) = 0.3872
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Cheers,
Stan H.
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Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

23members... majority vote takes at least 12

or at least 7 votes among the remaining 18

p = .50,  n = 18

P(x ≥ 7) = 1 – P(x ≤ 6)= 1-binomcdf(18,.50,6)