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#1 2013-12-01 05:44:15

am1212
Member
Registered: 2013-12-01
Posts: 6

Statistics Help- Sampling Distributions

I am taking an Elementary Statistics course.. I need to know the right answer and how to get the right answer to these problems. We are able to use excel to solve the problems. Any help would be appreciated!


Question 5:
Cans of regular Coca-Cola are labeled as containing 12oz, and a statistics student would like to see if this 12oz number is really believable. To do this, the student measured the contents of 8 randomly chosen cans, and found the mean volume to be 12.1.
Assuming that cans of Coke are filled so that the actual amounts are normally distributed with a mean of 12.00oz and a standard deviation of 0.09oz. Find the probability that a sample of 8 cans will have a mean amount of at least 12.1 oz.

I have no idea how to get the correct answer for this problem.. I ave tried multiple times and ways. 

Question 8:
Scores for men on the verbal portion of the SAT-I test are normally distributed with a mean of 509 and a standard deviation of 112.
(a)  If 1 man is randomly selected, find the probability that his score is at least 581.

I was able to figure this one out and the answer is 0.2601584 .
 
(b)  If 20 men are randomly selected, find the probability that their mean score is at least 581.

I am confused on how to find this answer..

Last edited by am1212 (2013-12-01 05:49:36)

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#2 2013-12-01 06:07:40

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions

Hi;

Question 5)

Since you say you are taking an elementary course I di it in the simplest manner possible. I am getting a probability of .13326


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#3 2013-12-01 06:21:15

am1212
Member
Registered: 2013-12-01
Posts: 6

Re: Statistics Help- Sampling Distributions

I've tried that answer as well but the program where we submit our answers tell me that's incorrect.

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#4 2013-12-01 06:22:48

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions

Did you round it?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#5 2013-12-01 06:25:27

am1212
Member
Registered: 2013-12-01
Posts: 6

Re: Statistics Help- Sampling Distributions

No, we're supposed to submit answers to 4 decimal places.

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#6 2013-12-01 06:31:19

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions

What did you round it to?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#7 2013-12-01 06:54:13

am1212
Member
Registered: 2013-12-01
Posts: 6

Re: Statistics Help- Sampling Distributions

I didn't round it. I submitted .13326 ; I also tried 13.326

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#8 2013-12-01 06:57:29

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions

Did you try .1333 or .1332?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#9 2013-12-01 07:43:46

am1212
Member
Registered: 2013-12-01
Posts: 6

Re: Statistics Help- Sampling Distributions

Both- that is not the correct answer. There must be another way to do the problem

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#10 2013-12-01 08:37:24

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions

Yes there is I will post it a little later because I have to go offline now.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#11 2013-12-01 12:29:45

am1212
Member
Registered: 2013-12-01
Posts: 6

Re: Statistics Help- Sampling Distributions

0.000837051 is the correct answer

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#12 2013-12-01 14:44:52

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,638

Re: Statistics Help- Sampling Distributions


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

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