Reference no: EM132394254

1. We want to construct a confidence interval for a population standard deviation. The population is known to be normally distributed. What distribution should we use?

A) Standard Normal Distribution, z

B) Bootstrapping

C)Chi-square Distribution, χ2

D)Student t Distribution, t

2. What is the critical value zα/2 for a 98% level of confidence? (Round to the nearest hundredth.)

3. What is χ2R for a sample of size n = 23 at the 95% level of confidence? (Round to the nearest thousandth.)

4. What is the margin of error for the confidence interval 0.123 < p < .147 ? (Round to the nearest thousandth.)

5. What is the value of p^ for the confidence interval 0.123 < p < .147 ? (Round to the nearest thousandth.)

6. What is the value of tα/2 for sample of size n = 39 at the 90% level of confidence? (Round to the nearest thousandth.)

7. What is the margin of error for a 95% confidence interval when p^ = 0.52 and n = 50 ? (Round to the nearest ten-thousandth.)

8. What is the lower limit of the 99% confidence interval for a population variance when s = 3, n = 20? (Round to the nearest ten-thousandth.)

9. A certain randomly selected sample of 125 registered voters showed that 20% of them voted in the most recent school board election. How many of these voters actually voted in that election?

10. We want to construct a confidence interval for a population mean. We want to be 95% confident with a margin of error of 1.5. We know that σ = 10.5. How large should our sample be?

11. In a CNBC-AP poll conducted in April 2010, 44% of those surveyed said that marijuana and alcohol should have the same level of governmental regulation. The poll has a margin of error of 4.3%. There were 1001 American adults in the survey. What is the confidence level for this poll? (Type the percentage rounded to the nearest hundredth without the % sign.)