AP Stats Identify Tests

A mayor is concerned about the percentage of city residents who express disapproval of his job performance.  His political committee pays for a newspaper ad, hoping to keep his disapproval rating below 21%.  They will use a follow up poll to access effectiveness.  What are the correct null and alternative hypotheses?

• Ho: p=.21
  Ha: p > .21

• Ho: p< .21
  Ha: p= .21

• Ho: p> .21
  Ha: p= .21

• Ho: p= .21
  Ha: p< .21

5% of trucks of a certain model have needed new engines after being driven between 0 and 100 miles.  The manufacturer hopes that the redesign of one of the engine's components has solved this problem.  Write the null and alternative hypotheses for this situation.

• Ho:  p< 0.05
  Ha:  p = 0.05

• Ho:  p = 0.05
  Ha:  p > 0.05

• Ho:  p = 0.05
  Ha:  p < 0.05

• Ho:  p > 0.05
  Ha:  p = 0.05

Which of the following represents the appropriate null & alternative hypotheses?
The mean height of women is greater than 64"

• H₀: μ > 64"
  Hₐ: μ ≠ 64"

• H₀: μ = 64"
  Hₐ: μ > 64"

• H₀: p > 64"
  Hₐ: p ≠ 64"

• H₀: p = 64"
  Hₐ: p > 64"

IF P(A and B) = P(A)P(B) then A and B are 

• Disjoint

• Disjoint and Independent

• Mutually Exclusive

• Independent

What does this symbol represent?

• sample mean

• population standard deviation

• population mean

• sample mew

What does this symbol represent?

• population mean

• population standard deviation

• parameter standard error

• proportion standard deviation

What tells you the number of standard deviations above or below the mean an observation is? 

• standard error

• z-score

• 68-95-99.7 Rule

• S

To test a claim about a mean, when the population standard deviation is unknown we use:

• z procedures

• Pythagorean Theorem

• t procedures

• np > 10 and n(1-p) > 10

Identify the correct null hypothesis:

• H₀: p = 0.50

• H₀: µ = 100

• H₀: p = 0.48

• H₀: µ = 96

We conclude "Fail to reject H₀". What could we use as our interpretation?

• The proportion of babies born male is not 0.50.

• There is not enough evidence to say that the proportion of babies born male is different from 0.50.

• There is not enough evidence to say that the proportion of babies born male is 0.50.