3I'S REVIEW QUIZ

Bedazzled Motor Company claims that Its new sedan, the Glitteratti, will average better than 26 miles per gallon in the city. Which of the following represents the appropriate null & alternative hypotheses?

• Ho: μ ≤ 26
  Ha: μ > 26 claim

• Ho: μ > 26 claim

  Ha: μ ≤ 26

• Ho: μ < 26

  Ha: μ ≥ 26 claim

• Ho: μ = 26
  Ha: μ < 26 claim

The owner of a soccer team claims that the average attendance at games is over 62,900. Which of the following represents the appropriate null & alternative hypotheses?

• Нo: μ < 62,900
  Ha: μ ≥ 62,900 claim
  

• Ho: μ = 62,900 claim
  Ha: μ < 62,900

• Ho: μ > 62,900
  Ha: μ ≤ 62,900 claim

• Ho: μ ≤ 62,900
  Ha: μ > 62,900 claim

The weight of the average 6th grade student's backpack (with books in it) is 18.4 lbs. What is the null and alternate hypothesis?

• Ho = 18.4 claim
  Ha = 18.4

• Ho < 18.4
  Ha > 18.4 claim

• Ho > 18.4
  Ha < 18.4 claim

• Ho = 18.4 claim
  Ha ≠ 18.4

According to official census figures, 8% of couples living together are not married. A researcher took a random sample of 400 couples and found that 9.5% of them are not married. Test at the 15% significance level if the current percentage of unmarried couples is different from 8%.

Which of the following statements accurately represents the hypothesis test conducted to determine if the current percentage of unmarried couples differs from 8%.

• The null hypothesis (HO) states that the percentage of unmarried couples is 9.5%, while the alternative hypothesis (H1) states that it is different from 8%.

• The null hypothesis (HO) suggests that the percentage of unmarried couples is 8%, while the alternative hypothesis (H1) indicates it is not equal to 8%.

• The null hypothesis (HO) asserts that the percentage of unmarried couples is less than 8%, whereas the alternative hypothesis (H1) states it is greater than 8%.

• The null hypothesis (HO) posits that the percentage of unmarried couples is 8%, and the alternative hypothesis (H1) argues that it is exactly 8%.

If you release 10 spiders into a room and measure how long it takes people to get out of the room,

what is the independent variable?

• The spiders

• The people

• The amount of time it takes the people to leave the room

• The room

What is the conclusion of the hypothesis test conducted to determine if the current percentage of unmarried couples differs from 8% at the 15% significance level?

• Reject the null hypothesis; there is evidence to suggest that the percentage of unmarried couples is different from 8%.

• Fail to reject the null hypothesis; there is not enough evidence to conclude that the percentage of unmarried couples differs from 8%.

• Accept the null hypothesis; the percentage of unmarried couples is 8%.

• Fail to reject the null hypothesis; the percentage of unmarried couples is exactly 8%.

A factory produces 500 items using a new machine. Upon inspection, 28 of them are found to be defective. The factory plans to discard the machine if there is significant evidence that the proportion of defective items exceeds 5%.

What is the calculated z-value for the hypothesis test?

• z = 0.54

• z = 1.50

• z = 1.89

• z ≈ 2.10

A factory produces 500 items using a new machine. Upon inspection, 28 of them are found to be defective. The factory plans to discard the machine if there is significant evidence that the proportion of defective items exceeds 5%.

What is the conclusion of the hypothesis test?

• Reject the null hypothesis; there is sufficient evidence to suggest that the proportion of defective items exceeds 5%.

• Fail to reject the null hypothesis; there is insufficient evidence to suggest that the proportion of defective items exceeds 5%.

• Reject the null hypothesis; the proportion of defective items is exactly 5%.

• Fail to reject the null hypothesis; the proportion of defective items is significantly lower than 5%

A factory produces 500 items using a new machine. Upon inspection, 28 of them are found to be defective. The factory plans to discard the machine if there is significant evidence that the proportion of defective items exceeds 5%.

At a significance level of 10%, what action should the factory take based on the hypothesis test?

• Retain the machine; there is insufficient evidence to suggest that the proportion of defective items exceeds 5%.

• Discard the machine; the proportion of defective items is significantly higher than 5%.

• Retain the machine; the proportion of defective items is exactly 5%.

• Discard the machine; there is insufficient evidence to determine the proportion of defective items.

What aspect you DON'T include in the problem description?

• The definition of the problem from theory or articles

• Evidence of the problem from surveys and observations

• The objectives of the research problem solution

• Gaps in existing knowledge about the problem