MATH 110 - Introduction to
Statistics Module 5
Exam
Exam Page 1
Suppose that you take a sample of size 50 from a population that is not normally distributed. Can the
sampling distribution of x̄ be approximated by a normal probability distribution?
Yes, the sample size can be approximated by a normal probablity ditribution because the sample size is
greater than 30.
Answer Key
Suppose that you take a sample of size 50 from a population that is not normally distributed.
Can the sampling distribution of x̄ be approximated by a normal probability distribution?
Yes. The sample size is greater than 30, therefore, we may approximate by a normal
probability distribution.
, Exam page 3
Suppose that you are attempting to estimate the annual income of 1200 families. In order to
use the infinite standard deviation formula, what sample size, n, should you use?
(n / N ) ≤0.05
N = 1200
n ≤ (0.05 x 1200 ) = 60
n ≤ 60
The sample size (n) has to be less than or equal to 60
n ≤ 60
The sample size (n) has to be less than or equal to 60
Answer Key
Suppose that you are attempting to estimate the annual income of 1200 families. In order to
use the infinite standard deviation formula, what sample size, n, should you use?
In order to use infinite standard deviation formula, we should have:
n≤0.05(1200)
n≤60
So, the sample size should be less than 60.
Statistics Module 5
Exam
Exam Page 1
Suppose that you take a sample of size 50 from a population that is not normally distributed. Can the
sampling distribution of x̄ be approximated by a normal probability distribution?
Yes, the sample size can be approximated by a normal probablity ditribution because the sample size is
greater than 30.
Answer Key
Suppose that you take a sample of size 50 from a population that is not normally distributed.
Can the sampling distribution of x̄ be approximated by a normal probability distribution?
Yes. The sample size is greater than 30, therefore, we may approximate by a normal
probability distribution.
, Exam page 3
Suppose that you are attempting to estimate the annual income of 1200 families. In order to
use the infinite standard deviation formula, what sample size, n, should you use?
(n / N ) ≤0.05
N = 1200
n ≤ (0.05 x 1200 ) = 60
n ≤ 60
The sample size (n) has to be less than or equal to 60
n ≤ 60
The sample size (n) has to be less than or equal to 60
Answer Key
Suppose that you are attempting to estimate the annual income of 1200 families. In order to
use the infinite standard deviation formula, what sample size, n, should you use?
In order to use infinite standard deviation formula, we should have:
n≤0.05(1200)
n≤60
So, the sample size should be less than 60.
