1. Last Saturday at ONYX Health Club 24/7 in Northfield, Ohio, 15 individuals were selected and the number of sit-ups that each could complete was recorded. The results are listed below. {27, 12, 18, 5, 16, 25, 30, 13, 35, 10, 1, 13, 33, 24, 22} (a) Find the point estimate of the population mean number of sit-ups. (Round your answer to 3decimals.)

(b) Calculate the margin of error. (Round your answer to 3 decimals.)

(c) Calculate the 95 percent confidence interval of the population mean number of sit-ups. (Round each value to 3 decimals.) [ , ]

2. A local company has 93insurance salespersons. The boss wants to know if the salespersons would prefer a weekend meeting instead of a meeting during the week. She asked 24of the salespersons if they would prefer a weekend meeting and 15of them said that they would prefer a weekend meeting. (a) Find the point estimate of the population proportion that would prefer a weekend meeting. (Round your answer to 3 decimals.)

(b) Calculate the margin of error. (Round your answer to 3 decimals.)

(c) Calculate the 99 percent confidence interval of the population proportion that would prefer a weekend meeting. (Round each numberto 3 decimals.) [ , ]

3. A coach wants to estimate the proportion of athletes who want to become coaches in the future. The error in estimating the proportion is to be less than 0.0106with a 92% level of confidence. The coach found a comparable study that reported that the population proportion was 0.387. What is the minimum required sample size?

4. A teacher wants to estimate the mean number of hours that her students study the day before a test. The error in estimating the mean is to be less than 0.8hours with a 90% level of confidence. The teacher found a similar study that stated that the standard deviation was 7.9hours. What is the minimum required sample size?

5. A sample of 255Lakewood residents were asked if they like the diversity of their city. 164of those surveyed said that they like Lakewood's diversity.

(a) Find the point estimate of the population proportion of Lakewood residents who like the city's diversity. (Round your answer to 3 decimals.)

(b) Calculate the margin of error. (Round your answer to 3 decimals.)

(c) Calculate the 98 percent confidence interval of the population proportion of Lakewood residents who like the city's diversity. (Round each value to 3 decimals.)

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6.According to a recent report, the mean income before taxes of 206 households in the U.S. was $65,100.40.The population standard deviation was known to be $7,589.33. (a) Find the point estimate of the population mean income.

(b) Calculate the margin of error. (Round to three decimals.)

(c) Calculate the 90 percent confidence interval of the population mean income. (Round each value to three decimals.

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7. The graph of a confidence interval is always

		two-tailed
		right-tailed
		dependent on the problem
		left-tailed

8.A margin of error is calculated by

		multiplying a chart value by a standard error
		adding a chart value to a standard error
		subtracting a chart value from a standard error
		dividing a chart value by a standard error

9. A confidence interval is constructed by taking a point estimate and adding and subtracting a

		chart value
		standard deviation
		margin of error
		standard error

10. The best estimate of a population parameter is a(n)

		forecasting tool
		sample statistic
		sample parameter
		educated guess