One survey found that 23% of its members had purchased shares directly through an initial public offering. In a sample of 12 members, what is the probability that three members have purchased in an initial public offering?

Question
Answer:
To calculate the probability that three out of 12 members have purchased shares directly through an initial public offering (IPO), we can use the binomial probability formula: P(X = k) = (n choose k) * p^k * (1 - p)^(n - k) Where: - P(X = k) is the probability of getting exactly k successes. - n is the number of trials or members in the sample (12 in this case). - k is the number of successes we're interested in (3 members purchasing through IPO). - p is the probability of success on a single trial (the probability that a member has purchased through IPO). In this case, p = 0.23 (23% expressed as a decimal), n = 12, and k = 3. Now, let's calculate the probability: P(X = 3) = (12 choose 3) * (0.23)^3 * (1 - 0.23)^(12 - 3) Using a calculator, you can calculate the binomial coefficient (12 choose 3) as: (12 choose 3) = 220 Now, plug the values into the formula: P(X = 3) = 220 * (0.23)^3 * (0.77)^9 P(X = 3) ≈ 0.2547 So, the probability that three out of 12 members have purchased shares directly through an initial public offering is approximately 0.2547, or about 25.47%.
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general 6 months ago 1801