Question

If you drew a random sample of size 40 from a population of students having a mean (μ) Math Achievement Test score of 200 and a standard deviation (σ) of 20

1.What would be the average of all the sample Math Aptitude means you could have obtained for samples of size 40? Mx= ?

2.Not all your possible sample averages would have been the same. What would be their “standard” distance from the population average of 200? σx= ?

3.If you had sampled an n=100 instead of 40, what would be the standard difference from 200 now?

Answer #1

Result:

If you drew a random sample of size 40 from a population of students having a mean (μ) Math Achievement Test score of 200 and a standard deviation (σ) of 20

1.What would be the average of all the sample Math Aptitude means you could have obtained for samples of size 40?

**Mx= 200**

2.Not all your possible sample averages would have been the same. What would be their “standard” distance from the population average of 200?

σx= σ /sqrt( n) = 20/sqrt(40)

**=3.16228**

3.If you had sampled an n=100 instead of 40, what would be the standard difference from 200 now?

σx= σ /sqrt( n) = 20/sqrt(100)

**=****2**

A simple random sample of size n=40 is obtained from a
population with μ = 50 a n d σ = 4. Does the population
distribution need to be normally distributed for the sampling
distribution of x ¯ to be approximately normally distributed? Why
or why not? What is the mean and standard deviation of the sampling
distribution?

Suppose that we take a random sample of size n from a population
having a mean μ and a standard deviation of σ. What is the
probability or confidence we have that our sample will be within
+/- 1 of the population mean μ?
(a) μ = 10, σ = 2, n = 25

A population has parameters μ=126.3μ=126.3 and σ=57.9σ=57.9. You
intend to draw a random sample of size n=221n=221.
What is the mean of the distribution of sample means?
μ¯x=μx¯=
What is the standard deviation of the distribution of sample
means?
(Report answer accurate to 2 decimal places.)
σ¯x=σx¯=

A population has parameters μ=126.3μ=126.3 and σ=57.9σ=57.9. You
intend to draw a random sample of size n=221n=221.
What is the mean of the distribution of sample means?
μ¯x=μx¯=
What is the standard deviation of the distribution of sample
means?
(Report answer accurate to 2 decimal places.)
σ¯x=σx¯=

Suppose that a random sample of size 64 is to be selected from a
population with mean 40 and standard deviation 5.
(a) What are the mean and standard deviation of the sampling
distribution?
μx =
σx =
(b) What is the approximate probability that x will be
within 0.4 of the population mean μ? (Round your answer to
four decimal places.)
P =
(c) What is the approximate probability that x will differ
from μ by more than 0.8?...

1. A sample size of 49 drawn from a population with a mean of 36
and a standard deviation of 15 for the size of an English class.
What is the probability the class will have greater than 40
a. .9693
b. .4693
c. .0808
d. .0307
2. A sample size of 49 drawn from a population with a mean of 36
and a standard deviation of 15 for the size of an English class.
What is the probability the...

A simple random sample of size 11 is drawn from a normal
population whose standard deviation is σ=1.8. The sample mean is
¯x=26.8.
a.) Construct a 85% confidence level for μ. (Round answers to two
decimal place.)
margin of error:
lower limit:
upper limit:
b.) If the population were not normally distributed, what
conditions would need to be met? (Select all that apply.)
the population needs to be uniformly distributed
σ is unknown
simple random sample
large enough sample size...

Suppose a simple random sample of size n=36 is obtained from a
population with μ= 89 and σ= 12. Find the mean and standard
deviation of the sampling distribution of X.
a) What is P (x > 91.4)?
b) What is P (x ≤ 84.8)?
c) What is P(86< x<93.3)?

Suppose a simple random sample of size n is obtained from a
population whose size is N and whose population proportion with a
specified characteristic is Complete parts (a) through (c) below. =
1000 = 2,000,000 p = 0.25. Click here to view the standard normal
distribution table (page 1).7 Click here to view the standard
normal distribution table (page 2).8 (a) Describe the sampling
distribution of p. A. Approximately normal, μ and p = 0.25 σ p ≈
0.0137...

Based on a simple random sample of size 90, an 84% confidence
interval for the unknown mean SAT MATH score, μμ, in some large
population is 517<μ<525517<μ<525.
Which of the following is/are correct interpretation(s) of this
confidence interval?There may be more than one correct answer; you
must check all correct answers in order to get credit for this
problem.
A. 84% of individuals in this sample have a mean
SAT MATH score between 517 and 525.
B. 84% of individuals...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 3 minutes ago

asked 6 minutes ago

asked 22 minutes ago

asked 30 minutes ago

asked 34 minutes ago

asked 34 minutes ago

asked 36 minutes ago

asked 39 minutes ago

asked 43 minutes ago

asked 44 minutes ago

asked 1 hour ago

asked 1 hour ago