got a stats question...last time nyc helped me

[doubles1]

nycgirl last time you helped me however i have another problem that I am needing help with...

i will gladly give sum karma

here is the problem:

What sample size is needed to estimate with 95 percent confidence the mean intake of calcium within 20 units of the true mean if the intake is normal with a variance of 1900 units.

thanks for any assistance.

-mark

 

[nycgirl]

Oh, confidence intervals. A bit of weak spot for me. I regression. Absolutely hate the confidence interval.

Give me a minute. I will give it a shot. If I'm not confident about my answer/help I will let you know. Definitely, go with someone else if they beat me to it.

How are you doing?

 

[doubles1]

im doing okay i am taking a test right now with using z and t tables and sample sizes and also hypothesis and alternate hypothesis.

the only thing i am having trouble on is that question and

What sample size would be required to estimate m to within ±3 with 95% confidence if the population standard deviation is 24.5?

and the choices are
769
124
257
91
2321

other than that i have a couple more questions to answer and i should be done with this test...ahhhhhhhhhhhhhhhhhhhhhhhhhh been working on it for about 3 hrs!!!

 

[EnderJE]

WTF? Are you surfing while taking the test? It is an in-home test or an in-class test? If it's in class, you've got the props, maing.

 

[doubles1]

hey its online test...i have 4 hrs to take it ...theres like 35 fuckin problems!!!!


nyc if you have aim or yahoo would you msg me...i will pm you my name!!

 

[doubles1]

hey you exceeded your pm's...

hey my yahoo name is

[email protected]

and aim

lucky5588

hit me up if you dont mind...

 

[nycgirl]

hey its online test...i have 4 hrs to take it ...theres like 35 fuckin problems!!!!


nyc if you have aim or yahoo would you msg me...i will pm you my name!!

I have msn.

Are these the only questions you are having issues with? You may have to guess on these.

 

[Smurfy]

cheater!

 

[doubles1]

umm well if you wouldnt mind msg'ng me i am impressed with your knowledge and wouldnt mind askin u a couple of things.

 

[doubles1]

hey NYC, if your not comfortable msgn me thats fine.

the last prob im working with is this...


Does the sample evidence indicate that the average time an employee stays with a company in their current positions is less than 3 years? A random sample of 50 employees yielded a mean of 2.79 years and s = .76. Use a = .01