Exam 3 Sample

Many small town are adding in stop signs to prevent accidents. A small town mayor believes that the proportion of accidents will fall below the current value of 0.65.

Specify the null and alternative hypotheses to test the police department’s claim.

• H₀: p = 0.65 a

  Hₐ: p ≠ 0.65

• H₀: p < 0.65

  Hₐ: p ≥ 0.65

• H₀: p ≤ 0.65

  Hₐ: p > 0.65

• H₀: p ≥ 0.65

  Hₐ: p < 0.65

It is generally believed that no more than 0.50 of stray animals are purposely left by their owners. A shelter owner feels this number is increasing. Identify the correct null and alternative hypotheses to test the shelter owner's claim.

• H₀: p = 0.50 and Hₐ: p ≠ 0.50

• H₀: p ≤ 0.50 and Hₐ: p > 0.50

• H₀: p ≥ 0.50 and Hₐ: p > 0.50

• H₀: p ≥ 0.50 and Hₐ: p < 0.50

If the p-value for a hypothesis test is 0.0189 and the chosen level of significance is α = 0.01, then the correct conclusion is to:

• reject the null hypothesis

• not reject the null hypothesis

• Not enough information.

An advertisement for a popular weight loss clinic suggests that participants in its new diet program lose, on average, more than 10 pounds. A consumer activists decides to test the authenticity of the claim. She follows the progress of 18 women who recently joined the weight reduction program. She calculates the mean weight loss of these participants as 10.8 pounds with a standard deviation of 2.4 pounds.

What is the test stat?

• z = 1.414

• t17 = -1.414

• t17 = 1.414

• z = -1.414

• z = 0.500

Tags

CCSS.HSS.IC.A.1

An advertisement for a popular weight loss clinic suggests that participants in its new diet program lose, on average, more than 10 pounds. A consumer activists decides to test the authenticity of the claim with an alpha value of 0.05. She follows the progress of 18 women who recently joined the weight reduction program. She calculates the mean weight loss of these participants as 10.8 pounds with a standard deviation of 2.4 pounds.

What is the critical value?

• 1.740

• 1.645

• -1.740

• 1.96

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.IC.B.5

Using the T-table, what is the estimated p-value for a two-tail test with a test stat of 2.06 and df of 20?

• 0.0375

• 0.075

• 0.15

• 0.035

Using a test stat for a hypothesis test where the population standard deviation is known.

What is the critical value for 0.05 level of significance for a lower tail test?

• 1.645

• -1.645

• ± 1.645

• 1.96

Tags

CCSS.HSS.ID.A.4

What is the Z α/2 for a 90% confidence interval of the population mean?

• 0.48

• 0.49

• 1.645

• 1.96

Tags

CCSS.HSS.IC.B.4

CCSS.HSS.ID.A.4

What table would you use for the following: You have a sample size of 15 and the population standard deviation is unknown. The sample standard deviation is 1.5. Assume the distribution is normal.

• Chi-square table

• F-table

• T-Table

• Z-Table

A researcher claims that the average time spent on social media by teenagers is more than 3 hours per day. A sample of 50 teenagers shows an average time of 3.2 hours with a standard deviation of 0.5 hours. What is the test statistic for this claim?

• t49 = 2.83

• z = 2.83

• t49 = 1.96

• z = 1.96

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.ID.A.4