Exam 9: Hypothesis Tests About the Mean and Proportion

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of 24 elements selected from the population produced a mean of 58.6 and a standard deviation of 13.4.The test is to be made at the 10% significance level.Assume the population is normally distributed. -Should you reject or fail to reject the null hypothesis in this test? (State your answer as "reject" or "fail to reject",but don't include the quotation marks.)

In a left-tailed hypothesis test,the sign in the alternative hypothesis is:

If the significance level of a hypothesis test is 5% we will reject the null hypothesis is the p-value is

In a hypothesis test with hypotheses and ,a random sample of 38 elements selected from the population produced a mean of 74.4.Assuming that 8.9 and the population is normally distributed,what is the approximate p-value for this test? (round your answer to four decimal places)

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of 20 elements selected from the population produced a mean of 67.8 and a standard deviation of 11.9.The significance level is 5%.Assume the population is normally distributed. -What is the p-value for this hypothesis test,rounded to four decimal places?

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of size 530 produced a sample proportion of 0.2755.The test is to be made at the 2% significance level. -What is the critical value of z?

The alternative hypothesis is a claim about a:

Use the following to answer questions : A company that manufactures light bulbs claims that its light bulbs last an average of 1,150 hours.A sample of 25 light bulbs manufactured by this company gave a mean life of 1,097 hours and a standard deviation of 133 hours.A consumer group wants to test the hypothesis that the mean life of light bulbs produced by this company is less than 1,150 hours.The significance level is 5%.Assume the population is normally distributed. -What is the critical value of t?

Use the following to answer questions : A researcher wants to test if the elementary school children spend less than 30 minutes per day on homework.A random sample of 64 children from the school shows that they spend an average of 24.5 minutes per day on homework.Assume that 15.3 minutes,and that the test is to be made at the 1% significance level. -What is the critical value of z?

The null hypothesis is a claim about a:

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of 24 elements selected from the population produced a mean of 58.6 and a standard deviation of 13.4.The test is to be made at the 10% significance level.Assume the population is normally distributed. -What is the value of the test statistic,t,rounded to three decimal places?

A researcher wants to test if the mean annual salary of all lawyers in a city is different than $110,000.The null hypothesis for this example will be that the population mean is:

Use the following to answer questions : A researcher wants to test if the mean annual salary of all lawyers in a city is different from $110,000.A random sample of 53 lawyers selected from the city reveals a mean annual salary of $114,000.Assume that $17,000,and that the test is to be made at the 1% significance level. -Should you reject or fail to reject the null hypothesis in this test? (State your answer as "reject" or "fail to reject",but don't include the quotation marks.)

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of size 481 produced a sample proportion of 0.4350.The test is to be made at the 5% significance level. -What is the critical value of z?

In a hypothesis test,a Type II error occurs when:

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of size 1,165 produced a sample proportion of 0.6160.The test is to be made at the 2.5% significance level. -What is the critical value of z?

Use the following to answer questions : In a hypothesis test with hypotheses H₀ : μ=90 and H₁ : μ ≠ 90 , a random sample of 103 elements selected from the population produced a mean of 94.3. Assume that σ = 22.1, and that the test is to be made at the 5% significance level. -What is the p-value for this hypothesis test,rounded to four decimal places?

Use the following to answer questions : A company that manufactures light bulbs claims that its light bulbs last an average of 1,150 hours.A sample of 25 light bulbs manufactured by this company gave a mean life of 1,097 hours and a standard deviation of 133 hours.A consumer group wants to test the hypothesis that the mean life of light bulbs produced by this company is less than 1,150 hours.The significance level is 5%.Assume the population is normally distributed. -Should you reject or fail to reject the null hypothesis in this test? (State your answer as "reject" or "fail to reject",but don't include the quotation marks.)

Use the following to answer questions : In a hypothesis test with hypotheses and ,a random sample of size 1,165 produced a sample proportion of 0.6160.The test is to be made at the 2.5% significance level. -Should you reject or fail to reject the null hypothesis in this test? (State your answer as "reject" or "fail to reject",but don't include the quotation marks.)

In a hypothesis test with hypotheses and ,a random sample of 131 elements selected from the population produced a mean of 131.6.Assuming that 18.8,what is the approximate p-value for this test? (round your answer to four decimal places)