Hypothesis testing practice

At the Chrysler manufacturing plant, there is a part that is supposed to weigh precisely 19 pounds. The engineers take a sample of parts and want to know if they meet the weight specifications. What are our null and alternative hypotheses?

• H_o : μ = 17, H_a : μ ≠ 19

• H_o : μ = 19, H_a : μ ≠ 19

• H_o : μ = 19, H_a : μ ≠ 17

• H_o : μ = 17, H_a : μ ≠ 17

The form of the alternative hypothesis can be:

• one-tailed

• two-tailed

• neither one nor two-tailed

• one or two-tailed

The value set for α is known as:

• the rejection level

• the acceptance level

• the significance level

• the error in the hypothesis test

The null hypothesis is denoted by...

• H_A

• H₀

• H₂O

• H_µ

The alternative hypothesis is denoted by...

• H_A

• H₀

• H₂O

• H_µ

What is the critical value (in a test about proportions) for a left-tailed test with α = 0.05 and n ≥ 30. 

• z₀ = -1.645
• z₀ = -2.33
• z₀ = -1.96
• z₀ = 2.58

When do you use a t-value instead of a z-value?

• When n < 30

• When n ≥ 30

• When all of the planets align

• When the teacher says so

Which of the following is the FIRST step of a hypothesis test?

• Check assumptions & conditions
• Find your test statistic
• State your conclusion
• State your null & alternative hypotheses

A study found that 11 out of 44 randomly selected adults said they agree that toddlers should not be taken out to eat at a restaurant. It was previously believed that 30% of adults agree that toddlers should not be taken out to eat at a restaurant. I there evidence to suggest an decrease in this rate? Find the z-score.

• -0.766

• 0.766

• -0.724

• 0.724

Conduct a test to determine whether or not the population proportion of voters in favor of proposal A is greater than 50%. In a random sample of 200 voters, 140 said that they were in favor of this proposal. Compute the test statistic.

• z = 7.708

• z = 5.66

• p = 7.7 x 10^-9

• None of the above