AP Statistics Unit 5 Review #1

The magazine Sports Illustrated asked a random sample of 750 Division I college athletes, "Do you believe performance enhancing drugs area problem in college sports?" Suppose that 30% of all Division I athletes think that these drugs are a problem. Let p-hat be the sample proportion who say that these drugs are a problem.
Which of the following are the mean and standard deviation of the sampling distribution of the sample proportion p-hat?

• Mean =0.30, SD = 0.017

• Mean= 0.30, SD = 0.55

• Mean= .30, SD= .0003

• Mean= 225, SD= 12.5

• Mean= 225, SD= 157.5

The magazine Sports Illustrated asked a random sample of 750 Division I college athletes, "Do you believe performance enhancing drugs area problem in college sports?" Suppose that 30% of all Division I athletes think that these drugs are a problem. Let p-hat be the sample proportion who say that these drugs are a problem.

Decreasing the sample size from 750 to 375 would multiply the standard deviation by...

• 2

• $\sqrt{2}$

• $\frac{1}{2}$

• $\frac{1}{\sqrt{2}}$

The magazine Sports Illustrated asked a random sample of 750 Division I college athletes, "Do you believe performance enhancing drugs area problem in college sports?" Suppose that 30% of all Division I athletes think that these drugs are a problem. Let p-hat be the sample proportion who say that these drugs are a problem.

The sampling distribution of is approximately Normal because...

• there are at least 7500 Division I college athletes

• np = 225 and n(1 - p) = 525

• a random sample was chosen

• the athletes' responses are quantitative

• the sampling distribution of p-hat always has this shape

In a congressional district, 55% of the registered voters are Democrats. Which of the following is equivalent to the probability of getting less than 50% Democrats in a random sample of size 100?

• $P\left(z<\frac{.50-0.55}{100}\right)$

• $P\left(z<\frac{0.55-0.50}{\sqrt{\frac{0.55\left(0.45\right)}{100}}}\right)$

• $P\left(z<\frac{0.50-0.55}{\sqrt{\frac{0.55\left(0.45\right)}{100}}}\right)$

• $P\left(z<\frac{0.50-0.55}{\sqrt{100\left(0.55\right)\left(0.45\right)}}\right)$

• $P\left(z<\frac{0.55-0.50}{\sqrt{100\left(0.55\right)\left(0.45\right)}}\right)$

A mayor wanted to see if the people in his town thought he was doing a good job.
Which choice best represents a statistic?

• The percentage of all townspeople who believe the mayor is doing a good job.
• The percentage of townspeople surveyed who believe the mayor is doing a good job.
• All townspeople.
• A random selection of 100 townspeople.

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.3

CCSS.HSS.IC.B.4

A survey company was trying to see if people in a state thought the pollution was too high.
Which choice best represents a parameter?

• All people in the state.
• Percentage of all people in the state who thought the pollution was too high.
• 500 randomly selected residents of the state.
• 71% of the residents surveyed thought the pollution was too high.

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

The 40 yards sprint times for a soccer team are found to be normally distributed with a mean of 5.2 seconds and a standard deviation of 0.3 seconds.  What is the z-score for a player who runs a time of 5.6 seconds?

• -1.33
• 1.33
• 0.88
• 1.02

Tags

CCSS.HSS.ID.A.4

μ = 70 , σ = 8 , X = 50 . Find z score

• 2.5
• -2.5
• 5.2
• -5.2

Tags

CCSS.HSS.ID.A.4

The Gallup Poll asked a random sample of 1785 adults whether they attended church during the past week.  Let p-hat be the proportion of people in the sample who attended church.  A newspaper report claims that 40% of all U.S. adults went to church last week.  Suppose this claim is true. 
What is the mean of the sampling distribution of p-hat?

• 0.4
• 0.44
• 0.56
• 0.6

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.MD.A.2

28% of all Woodrow students believe Monday will be snow day. You take a sample of 50 students and find that 15 of them believe Monday will be a snow day. What does 50 represent? 

• n
• P
• phat
• standard deviation

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4