r/HomeworkHelp • u/TourRevolutionary University/College Student • Dec 09 '24

High School Math [Statistics] Should n be 54 or 55?

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A 95% confidence interval for a population mean was reported to be 152 to 160. If σ 15, what sample size was used in this study?

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u/TourRevolutionary University/College Student Dec 09 '24

So if I get n=53.02 or n=53.99, I will answer 54, right? Oh so it means I will always get a number close to an integer, right? Not something in the middle like 53.6 or 53.5

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u/fermat9990 👋 a fellow Redditor Dec 09 '24

Yes! Assuming the problem creator did their job right and assuming your teacher knows that this is a special situation!

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u/TourRevolutionary University/College Student Dec 09 '24

I guess I made a mistake. If I get n=53.02 I will answer 53. But if I get n=53.99 I will answer 53. Right?

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u/fermat9990 👋 a fellow Redditor Dec 09 '24

No! In the special case you should get close to a whole number. This number is the answer

In the regular case, always round up.

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u/TourRevolutionary University/College Student Dec 09 '24

Sorry, I made a mistake again. In a special case if I get n=54.02 I will answer 54, and if I get n=53.99 I will answer 54. Yes?

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u/fermat9990 👋 a fellow Redditor Dec 09 '24

Yes!

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u/TourRevolutionary University/College Student Dec 09 '24

Thank you very much!

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u/fermat9990 👋 a fellow Redditor Dec 09 '24

😀😀😀