elementary statistics set 2

sassytonigirl · 2016-02-06 09:20:09

6.
In a sample of seven cars, each car was tested for nitrogen-oxide emissions (in grams per mile) and the following results were obtained: 0.16, 0.12, 0.17, 0.11, 0.15, 0.16, 0.18. Assuming that this sample is representative of the cars in use, construct a 98% confidence interval estimate of the mean amount of nitrogen-oxide emissions for all cars. If the EPA requires that nitrogen-oxide emissions be less than 0.165 g/mi, can we safely conclude that this requirement is being met?

What is the confidence interval estimate of the mean amount of nitrogen-oxide emissions for all cars?
_______g/mi<μ<______ g/mi (Round to three decimal places as needed.)

Can we safely conclude that the requirement that nitrogen-oxide emissions be less than 0.165 g divided by mig/mi is being met?

A. No, because the confidence interval does not contain 0.165 g/mi.
B. Yes, we can definitely conclude that the requirement is met for all cars.
C. Yes, because the confidence interval contains 0.165 g/mi.
D. No, it is possible that the requirement is being met, but it is also very possible that the mean is not less than 0.165 g/mi.

7.
In order to estimate the mean amount of time computer users spend on the internet each month, how many computer users must be surveyed in order to be 90% confident that your sample mean is within 13 minutes of the population mean? Assume that the standard deviation of the population of monthly time spent on the internet is 228 min. What is a major obstacle to getting a good estimate of the population mean? Use technology to find the estimated minimum required sample size.
The minimum sample size required is ________ computer users. (Round up to the nearest whole number.)

What is a major obstacle to getting a good estimate of the population mean?
A. There may not be 833 computer users to survey.
B. The data does not provide information on what the computer users did while on the internet.
C. It is difficult to precisely measure the amount of time spent on the internet, invalidating some data values.
D. There are no obstacles to getting a good esitmate of the population mean.

8.
If we find that there is a linear correlation between the concentration of carbon dioxide in our atmosphere and the global temperature, does that indicate that changes in the concentration of carbon dioxide cause changes in the global temperature?

Choose the correct answer below.
A. Yes. The presence of a linear correlation between two variables implies that one of the variables is the cause of the other variable.
B. No. The presence of a linear correlation between two variables does not imply that one of the variables is the cause of the other variable.

Many thanks to anyone that helps me. This is not something I do to copy....I do my own work as I have to turn in all the steps worked out and I like to compare my answers because I know very very little about this stuff. I am only taking this class because I must to proceed in my graduate class. I am not a math student, I am a nurse. It is a required class and it has been 18 years since I've had any math and it is online so I am having to self-teach all of it to myself. Thanks for your help.

Last edited by sassytonigirl (2016-02-06 09:36:45)

sassytonigirl · 2016-02-07 10:29:11

Anyone care to help me?

sassytonigirl · 2016-02-07 15:57:06

#6
I got.... 0.119 < u < 0.181
and... D-NO IT IS POSSIBLE THAT THE REQUIREMENT IS BEING MET.....

#7
833
and D - there are no obstacles to getting a good....

#8
I got.....B-No the presence of a linear correlation between 2 variables ........

bobbym · 2016-02-07 15:57:22

Hi;

Choose B for 8.

Math Is Fun Forum

#1 2016-02-06 09:20:09

elementary statistics set 2

#2 2016-02-07 10:29:11

Re: elementary statistics set 2

#3 2016-02-07 15:57:06

Re: elementary statistics set 2

#4 2016-02-07 15:57:22

Re: elementary statistics set 2

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