Hypothesis Testing Means and Proportions

Which of the following shows a right-tailed test?

• Ha: µ < 15

• H₀: µ < 15

• Ha: µ > 15

• H₀: µ > 15

A large university is curious if they should build another cafeteria. They plan to survey a sample of their students to see if there is strong evidence that the proportion interested is higher than 40%, in which case they would consider building the new cafeteria. Here are the hypotheses they'll use:
H_0: p = 0.40 H_a: p >0.40 
Which of the following would be the consequence of a Type I error?

• They don't consider building the new cafeteria when they should.

• They don't consider building a new cafeteria when they shouldn't.
  

• They consider building a new cafeteria when they shouldn't.
  

• They consider building a new cafteria when they should.
  

• A
• B
• C
• D

• A
• B
• C
• D

Identify the correct null hypothesis:

• H₀: p = 0.50

• H₀: µ = 100

• H₀: p = 0.48

• H₀: µ = 96

About 76% of college professors said that if they could pick a career over again, they would choose to be a professor again. A random sample of 59 college professors in Colorado showed that 47 claim they would choose college teaching again. Does this indicate the proportion of professors in Colorado who would choose the career again is greater than the national rate of 76%? Use a 1% level of significance. 

• Do not reject H₀ (z = 0.76)

• Reject H₀ (z = 1.45)

• Do not reject H₀ (z = 1.45)

• Reject H₀ (z = 0.6)

A large nationwide poll recently showed an unemployment rate of 9% in the US. The mayor of a local town wonders if this is true for her town, so she plans to take a sample of residents to see if the unemployment rate is significantly different than 9% in her town. Here are the hypotheses:
H_0: p e0.09
Which of the following would be a type I error?

• She concludes the town's unemployment rate is not 9% when it actually is.

• She concludes the town's unemployment rate is not 9% when it actually is not.
  

• She concludes the town's unemployment rate is 9% when it actually is.
  

• She concludes the town's unemployment rate is 9% when it actually is not.
  

• The soil is actually safe and construction continues

• The soil is actually safe and construction stops

• The soil is actually unsafe and construction continues

• The soil is actually unsafe and construction stops

• A
• B
• C
• D

A level of significance of 5% means:

• There's a 5% chance we're wrong

• There's a 5% chance we'll be wrong if we fail to reject the null hypothesis

• There's a 5% chance we'll be wrong if we reject the null hypothesis.

• There's a 5% chance you'll get an A on the test.