Question 1

Consistent with the basic premise of a representative sample, if a given population consists of 60% women, your sample should have
A)40% men.
B)no less than 60% women.
C)an equal number of men and women.
D)whatever composition of men and women that you can find.

Accepted Answer

A representative sample should reflect the composition of the population, so if the population is 60% women, the sample should be 40% men to maintain the same ratio.

Question 2

In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could.It is known the population mean $\mu$ is 20 with $\sigma_{X}=8$ The scores for the men from the retirement community are given below.Use a two-tailed rejection region with a total area of 0.05.What is the z- value?

Accepted Answer

The answer of In a test of physical fitness, a...

Question 3

An article in a professional journal reports the z­score for the study's sample mean was -1.4.The authors also reported their sample mean was 97 with a sample size of 49 and the population mean was 102.However, they did not give the population standard deviation.What was their population standard deviation?

Accepted Answer

The answer of An article in a professional journal reports...

Question 4

In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could.It is known the population mean $\mu$ is 20 with $\sigma_{X}=8$ The scores for the men from the retirement community are given below.Use a two-tailed rejection region with a total area of 0.05.What critical value should you use?

Accepted Answer

The answer of In a test of physical fitness, a...

Question 5

The mean of the population $\sigma_{X}^{2}=100$ $(\mu)$ is 200 on a test measuring math skills of middle school students.The variance is
.The test scores for the students in Mr.Petri's class at Suburban Middle School are given below.Use a
rejection region with a probability of 5% only in the upper tail.What is the sample mean?

Accepted Answer

The answer of The mean of the population $\sigma_{X}^{2}=100$ $(\mu)$...

Question 6

The mean of the population $\sigma_{X}^{2}=100$ $(\mu)$ is 200 on a test measuring math skills of middle school students.The variance is
.The test scores for the students in Mr.Petri's class at Suburban Middle School are given below.Use a
rejection region with a probability of 5% only in the upper tail.What is the standard error of the mean?

Accepted Answer

The answer of The mean of the population $\sigma_{X}^{2}=100$ $(\mu)$...

Question 7

The range of probabilities
A)must be between 0 and 1.
B)is limitless.
C)is between 0 and 100.
D)must be at least 0, but it has no higher limit.

Accepted Answer

Probabilities range from 0 to 1, where 0 indicates impossibility and 1 indicates certainty.

Question 8

If your critical value is ±1.96 and your z-value is -2.44, do you reject the sample mean represents the underlying population or not?

Accepted Answer

The answer of If your critical value is ±1.96 and...

Question 9

In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could.It is known the population mean $\mu$ is 20 with $\sigma_{X}=8$ The scores for the men from the retirement community are given below.Use a two-tailed rejection region with a total area of 0.05.What is the standard error of the mean?

Accepted Answer

The answer of In a test of physical fitness, a...

Question 10

In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could.It is known the population mean $\mu$ is 20 with $\sigma_{X}=8$ The scores for the men from the retirement community are given below.Use a two-tailed rejection region with a total area of 0.05.What is the sample mean?

Accepted Answer

The answer of In a test of physical fitness, a...

Question 11

If the population variance $\left(\sigma_{X}^{2}\right)$ is 36, what is the standard error of the mean for a sample size of 144?

Accepted Answer

The answer of If the population variance $\left(\sigma_{X}^{2}\right)$ is 36,...

Question 12

When you see the symbol "p," it refers to
A)probability.
B)population.
C)percentile.
D)power.

Accepted Answer

The symbol "p" is commonly used to denote probability in statistical and mathematical contexts.

Question 13

What is the probability of a sample mean below z = +1.2?

Accepted Answer

The answer of What is the probability of a sample...

Question 14

Your professor told the class that, typically, 20% of the class receives As, 20% Bs, 35% Cs, 10% Ds, and 15% Fs.What is the probability the student sitting next to you will receive an A or an F? Put your answer in the form of a proportion.

Accepted Answer

The answer of Your professor told the class that, typically,...

Question 15

If the standard error of the mean is 18 and the N is 36, what is $\sigma_{X}$ ?

Accepted Answer

The answer of If the standard error of the mean...

Question 16

What is the probability of scores between the mean and z = 2.28?

Accepted Answer

The answer of What is the probability of scores between...

Question 17

Suzy is about to pick a cookie from a cookie jar.The cookie jar contains 4 chocolate chip, 3 vanilla, 2 ginger snap, and 1 sugar cookie.What is the probability that Suzy will not pick a vanilla cookie?
A).7
B).3
C)7
D)3

Accepted Answer

The total number of cookies is 4 (chocolate chip) + 3 (vanilla) + 2 (ginger snap) + 1 (sugar) = 10. The probability of not picking a vanilla cookie is the number of non-vanilla cookies (4 + 2 + 1 = 7) divided by the total number of cookies (10), which equals 0.7 or 7/10.

Question 18

What is the probability of getting a sample mean between 500 and 520 if the population mean is 500 and the standard deviation of the sampling distribution the standard error of the mean) is 20?

Accepted Answer

The answer of What is the probability of getting a...

Question 19

Suppose you flip a fair coin five times and get a "heads" each time.Your friend insists that your next flip certainly will come up as "tails." Is your friend correct?
A)No, though the gambler's fallacy makes us think this, it is not a guarantee that the next flip will be "tails."
B)Yes, due to the gambler's fallacy.
C)No, it probably is impossible to get "tails" with this particular coin.
D)While you should get "tails," you're probably more likely to get "heads."

Accepted Answer

Each coin flip is an independent event with a 50/50 chance of landing on heads or tails, regardless of previous outcomes. The gambler's fallacy is the incorrect belief that previous events can affect the outcome of a future event that is truly random.

Question 20

If the population mean is 132, the sample mean is 136, $\left(\sigma_{X}^{2}\right)$ = 40, and N = 18, what is z?

Accepted Answer

The answer of If the population mean is 132, the...

Quiz 6: Using Probability to Make Decisions About Data

Consistent with the basic premise of a representative sample, if a given population consists of 60% women, your sample should have

The range of probabilities

If your critical value is ±1.96 and your z-value is -2.44, do you reject the sample mean represents the underlying population or not?

If the population variance (σX2)\left(\sigma_{X}^{2}\right)(σX2​) is 36, what is the standard error of the mean for a sample size of 144?

When you see the symbol "p," it refers to

What is the probability of a sample mean below z = +1.2?

Your professor told the class that, typically, 20% of the class receives As, 20% Bs, 35% Cs, 10% Ds, and 15% Fs.What is the probability the student sitting next to you will receive an A or an F? Put your answer in the form of a proportion.

If the standard error of the mean is 18 and the N is 36, what is σX\sigma_{X}σX​ ?

What is the probability of scores between the mean and z = 2.28?

Suzy is about to pick a cookie from a cookie jar.The cookie jar contains 4 chocolate chip, 3 vanilla, 2 ginger snap, and 1 sugar cookie.What is the probability that Suzy will not pick a vanilla cookie?

What is the probability of getting a sample mean between 500 and 520 if the population mean is 500 and the standard deviation of the sampling distribution the standard error of the mean) is 20?

Suppose you flip a fair coin five times and get a "heads" each time.Your friend insists that your next flip certainly will come up as "tails." Is your friend correct?

If the population mean is 132, the sample mean is 136, (σX2)\left(\sigma_{X}^{2}\right)(σX2​) = 40, and N = 18, what is z?

If the population variance $\left(\sigma_{X}^{2}\right)$ is 36, what is the standard error of the mean for a sample size of 144?

If the standard error of the mean is 18 and the N is 36, what is $\sigma_{X}$ ?

If the population mean is 132, the sample mean is 136, $\left(\sigma_{X}^{2}\right)$ = 40, and N = 18, what is z?