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Mean, Range, Standard Deviation, Confidence Interval Calculations

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Assume the following sample data:

LENGTH (FT) SAMPLE 1
207.495 247.725 345.33 257.175
198.855 166.185 326.295 233.01
209.25 177.12 173.07 180.36
252.315 182.655 186.975 233.955
192.915 216 250.95 207.09
209.25 312.12 209.25 247.725

1. Calculate and explain the sample mean.
2. Calculate and explain the standard deviation.
3. Calculate and explain the range.
4. Calculate the 95% confidence interval for the mean.
5 Determine if the sample size is adequate to study the population if you assume E=50 FT.

6. Determine the probability of a sample point being between 250 - 300 FT.
7. Determine the probability of a sample point being between 175 - 200 FT.
8. Discuss differences between descriptive and inferential statistics.
9. Discuss the differences between a population and a sample.
10. Distinguish a parameter from a statistic.

By hand, perform a one sample t test to determine if this sample (above sample 1) could have come from a population where the population mean = 245 feet.

11. H0:
12. H1
13. t CRITICAL:
14. t CALCULATED:
15. DECISION
16. EXPLANATION OF DECISION

LENGTH (FT) SAMPLE 2
210.495 253.725 349.33 260.175
204.855 170.185 329.295 233.01
210.25 188.12 183.07 189.36
260.315 190.655 196.975 243.955
199.915 231 250.95 217.09
215.25 312.12 215.25 252.725

Use Excel to perform a two sample t test to determine if this sample (above SAMPLE 2) could have come from the same population that the sample in the previous question (SAMPLE 1) came from.

17. H0:
18. H1:
19. t CRITICAL
20. t CALCULATED:
21. DECISION:
22. EXPLANATION OF DECISION
23. p VALUE AND ITS MEANING

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https://brainmass.com/business/strategy-and-business-analysis/mean-range-standard-deviation-confidence-interval-calculations-141842

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The solution examines mean, range, standard deviation, confidence interval calculations.

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