Question 1: A random sample of133observations produced a sample mean of29. Find the critical and observed values ofzfor the following test of hypothesis using=0.1.The population standard deviation is known to be5and the population distribution is normal.

H0:=28versusH1:>28.

Round your answers to two decimal places.

z critical=

Enter your answer; z_critical

z observed=

Question 2: According to an estimate, the average total parent and student debt for new college graduates was $34,400in 2010-11 (Time, October 31, 2011). A random sample of475of this year's graduates showed that their average such debt is $38,000with a standard deviation of $5350. Do the data provide significant evidence at a3% significance level to conclude that the current average total parent and student debt for new graduates is higher than $34,400? Use both thep-value approach and the critical-value approach.

Use thep-value approach. Use thetdistribution table to find a range for thep-value. Enter the exact values for the range.

Enter your answer; the range for the p-value, lower bound

<p-value <

Enter your answer; the range for the p-value, upper bound

Use the critical-value approach. Round your observed value to four decimal places, and your critical value to two decimal places.

Observed value =

Enter you answer; Observed value

Critical value =

Enter you answer; Critical value

Question 3:According to the U.S. Census Bureau, 11% of children in the United States lived with at least one grandparent in 2009 (USA TODAY, June 30, 2011). Suppose that in a recent sample of1560children,224were found to be living with at least one grandparent. At a2.5% significance level, can you conclude that the proportion of all children in the United States who currently live with at least one grandparent is higher than 11%? Use both thep-value and the critical-value approaches.

Round your answers for the observed value ofzand the critical value ofzto two decimal places, and thep-value to four decimal places.

z observed=

Enter you answer; z_observed

p-value =

Enter you answer; p-value

Critical value =

Enter you answer; Critical value

Question 4:According to aNew York Times/CBS News poll conducted during June 24-28, 2011, 55% of the American adults polled said that owning a home is avery important partof the American Dream (The New York Times, June 30, 2011). Suppose this result was true for the population of all American adults in 2011. In a recent poll of1820American adults,62% said that owning a home is avery important partof the American Dream. Perform a hypothesis test to determine whether it is reasonable to conclude that the percentage of all American adults who currently hold this opinion is higher than 55%. Use a5% significance level, and use both thep-value and the critical-value approaches.

Round your answers for the observed value ofzand the critical value ofzto two decimal places, and thep-value to four decimal places.

z observed=

Enter you answer; z_observed

p-value =

Enter you answer; p-value

Critical value =

Enter you answer; Critical value

Question 5: ConsiderH0:=72versusH1:>72.A random sample of16observations taken from this population produced a sample mean of76.0. The population is normally distributed with=6.

a.Calculate thep-value. Round your answer to four decimal places.

p=

Question 6: A random sample of107observations produced a sample mean of33. Find the critical and observed values ofzfor the following test of hypothesis using=0.01.The population standard deviation is known to be7and the population distribution is normal.

H0:=28versusH1:28.

Round your answers to two decimal places.

z critical left=

Enter your answer; z_critical left

z critical right=

Enter your answer; z_critical right

z observed=

Question 7:The manufacturer of a certain brand of auto batteries claims that the mean life of these batteries is45months. A consumer protection agency that wants to check this claim took a random sample of24such batteries and found that the mean life for this sample is43.00months. The lives of all such batteries have a normal distribution with the population standard deviation of4.5months.

Find thep-value for the test of hypothesis with the alternative hypothesis that the mean life of these batteries is less than45months.

Round your answer to four decimal places.

p=

Enter your answer in accordance to the question statement