# Question: A random sample of 80 observations results in 50 successes

A random sample of 80 observations results in 50 successes.

a. Construct the 95% confidence interval for the population proportion of successes.

b. Construct the 95% confidence interval for the population proportion of failures.

a. Construct the 95% confidence interval for the population proportion of successes.

b. Construct the 95% confidence interval for the population proportion of failures.

**View Solution:**## Answer to relevant Questions

Assume =1 0.6 in a sample of size n = 50.a. Construct the 95% confidence interval for the population proportion.b. What happens to the margin of error if the above sample proportion is based on n = 200 instead of n = 50?An economist reports that 560 out of a sample of 1,200 middle-income American households actively participate in the stock market.a. Construct the 90% confidence interval for the proportion of middle-income Americans who ...One in five 18-year-old Americans has not graduated from high school (The Wall Street Journal, April 19, 2007). A mayor of a northeastern city comments that its residents do not have the same graduation rate as the rest of ...A budget airline wants to estimate what proportion of customers would consider paying $12 for in-light wireless access. Given that the airline has no prior knowledge of the proportion, how many customers would it have to ...The following table shows the annual returns (in percent) for the Vanguard Energy Fund.Year Return2005...... 44.602006...... 19.682007...... 37.002008...... 242.872009...... 38.36a. Calculate the point estimate for ยต.b. ...Post your question