AnswersNC-Math 4Sampling Distribution of the Sample Proportion

Sampling Distribution of the Sample Proportion Answers

13 verified answers1 views
1
Free Preview

A large university with over 40,000 students recently took a survey in which 31% of the students claimed to exercise at least 3 times a week. A simple random sample of 250 students was selected. Let = the proportion of students in the sample who claimed to work out at least 3 times a week.What is the shape of the sampling distribution of and why?

Question illustration
A
approximately Normal, because all sampling distributions are approximately Normal
B
approximately Normal, because we would expect at least 10 success and 10 failures
C
skewed to the right, because 0.31 is lower than 0.5
D
skewed to the left, because 0.31 is lower than 0.5
2
Free Preview

difference in the two sample means ✔ difference in the two sample proportionssample meanssample proportions

A
difference in the two sample means
B
✔ difference in the two sample proportions
C
sample means
D
sample proportions
3

✔ typically varyvary exactly

A
✔ typically vary
B
vary exactly
4

means✔ proportions

A
means
B
✔ proportions
170690

A recent survey of the 1,800 students at a local high school revealed that 12% of the students believe that uniforms should be worn in schools. A simple random sample of 80 students is taken.

Answers:
The shape would best be described as with a mean of and a standard deviation of approximately .:skewed right
The shape would best be described as with a mean of and a standard deviation of approximately .:0.12
The shape would best be described as with a mean of and a standard deviation of approximately .:0.04
170691

Approximately 68% of the samples of size 150 will fall between 27% and 35% of the students claiming they exercise at least 3 times a week.The proportion of the sample who work out at least 3 times a week is 0.04.In simple random samples of size 150, the sample proportion of students who exercise at least 3 times a week will typically vary by about 0.04 from the true proportion of 0.31.In simple random samples of size 150, the sample proportion of students who exercise at least 3 times a week will always vary by exactly 0.04 from the true proportion of 0.31.

A
Approximately 68% of the samples of size 150 will fall between 27% and 35% of the students claiming they exercise at least 3 times a week.
B
The proportion of the sample who work out at least 3 times a week is 0.04.
C
In simple random samples of size 150, the sample proportion of students who exercise at least 3 times a week will typically vary by about 0.04 from the true proportion of 0.31.
D
In simple random samples of size 150, the sample proportion of students who exercise at least 3 times a week will always vary by exactly 0.04 from the true proportion of 0.31.
170694

In the US, 77% of all teens have a TV in their bedrooms, while 59% of all teens in Spain have them. A simple random sample of 500 teens from the US and 300 from Spain are selected and all are asked whether they have a TV in their bedrooms. Let be the difference in the sample proportions of teens with a TV in their bedrooms, where is the sample proportion of US teens with a TV in their bedrooms and is the sample proportion of Spanish teens with a TV in their bedrooms.

Answers:
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:500
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:difference in the two sample proportions
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:typically vary
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:proportions
170695

In the US, 77% of all teens have a TV in their bedrooms, while 59% of all teens in Spain have them. A simple random sample of 500 teens from the US and 300 from Spain are selected and all are asked whether they have a TV in their bedrooms. Let be the difference in the sample proportions of teens with a TV in their bedrooms, where is the sample proportion of US teens with a TV in their bedrooms and is the sample proportion of Spanish teens with a TV in their bedrooms.

Question illustration
Answers:
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:500
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:difference in the two sample proportions
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:typically vary
In random samples of size of US and Spanish teens, the will by about 0.034 from the true difference in of 0.18.:proportions

Did you find these answers helpful?