Ans: Solve Probability Problem: 80 Women in 150 People Sampled

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In summary, the probability of selecting a woman in a random sample of 150 people is 53.33%. Based on this, we can expect 80 women to be in the sample. The probability of selecting a man is 46.67%. If the first person selected was a man, the probability of selecting a woman becomes 53.69%. If the sample size is increased to 200 people, the probability of selecting a woman becomes 40%.
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statsluke
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I would really appreciate any help with answering this problem. Thank you.

150 people doing pre-start checks are randomly sampled. We find that 80 of the people sampled are women. At a significance level of 0.05, can we conclude that more women than men do pre-start checks?
 
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depends on your pop'n size.
 
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To solve this probability problem, we first need to calculate the probability of randomly selecting 80 women out of 150 people. This can be done using the binomial distribution formula, which is P(x) = nCx * p^x * (1-p)^(n-x), where n is the total number of people sampled, x is the number of women, and p is the probability of selecting a woman.

In this case, n = 150, x = 80, and p = 0.5 (assuming an equal probability of selecting a man or a woman). Plugging these values into the formula, we get P(80 women) = 150C80 * 0.5^80 * (1-0.5)^(150-80) = 0.035.

Next, we need to determine the critical value for a significance level of 0.05. This can be done using a statistical table or a calculator, and in this case, the critical value is 1.96.

Since the calculated probability of 0.035 is less than the critical value of 1.96, we can reject the null hypothesis and conclude that there is a significant difference between the number of women and men doing pre-start checks. In other words, at a significance level of 0.05, we can say with 95% confidence that there are more women than men doing pre-start checks.

I hope this helps with solving the probability problem. Let me know if you have any further questions. Good luck!
 

FAQ: Ans: Solve Probability Problem: 80 Women in 150 People Sampled

What is the probability of selecting a woman in a random sample of 150 people?

The probability of selecting a woman in a random sample of 150 people is 80/150 or 53.33%.

How many women are expected to be in a random sample of 150 people?

Based on the given information, we can expect 80 women to be in a random sample of 150 people.

What is the probability of selecting a man in a random sample of 150 people?

The probability of selecting a man in a random sample of 150 people is 70/150 or 46.67%.

What is the probability of selecting a woman if the first person selected was a man?

Since the sample size decreases to 149 after selecting a man as the first person, the probability of selecting a woman becomes 80/149 or 53.69%.

How does the probability of selecting a woman change if the sample size is increased to 200 people?

If the sample size is increased to 200 people, the probability of selecting a woman becomes 80/200 or 40%.

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