# math help

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Find the 95% confidence interval for the difference between two means based on this information about two samples. Assume independent samples from normal populations. (Use conservative degrees of freedom.) (Give your answers correct to two decimal places.)

Sample Number Mean Std. Dev.
1 27 39 21
2 16 26 35

This is what I have got so far. (27-1)X21squared + (16-1) X35squared divided by 27+16-2=12160.55556 then I sqrt 1/27 + 1/16=.3154949081, then 39-26/? x.315494981 now I am stuck???

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Is that two table or one table

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(-7.02, 33.02)

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It is a 2 samples, those answers are not right, but I desperately need your help. I do appreciate your help.

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I am sorry those answers were right, I was putting them on another proboem that I have, and I need your help on it, my sample 1 Number is 22, mean 31, and Std dev. 28, Second sample is Number 25, mean 25, Std. Dev. 35. I get as far as I did on the one above and that is as far as I can go. Thank goodness this is the last problem like this to do. Confidence 98%. Again thank you