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steps on STATCRUNCH Listed below are time intervals​ (min) between eruptions of a geyser. Assume that...

steps on STATCRUNCH

Listed below are time intervals​ (min) between eruptions of a geyser. Assume that the​ "recent" times are within the past few​ years, the​ "past" times are from around 20 years​ ago, and that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. Does it appear that the mean time interval has​ changed? Is the conclusion affected by whether the significance level is 0.10 or 0.01​?

Recent 78 90 88 79 58 101 61 86 69 89 83 82 55 82 73 103 61

Past 88 89 93 94 65 86 84 92 87 91 89 91

Let mu1 be the recent times and let mu2 be the past times. What are the null and alternative​ hypotheses?

Calculate the test statistic. t-equals nothing ​(Round to two decimal places as​ needed.) Find the​ P-value. ​P-value equals nothing ​(Round to three decimal places as​ needed.) Make a conclusion about the null hypothesis and a final conclusion that addresses the original claim. Use a significance level of 0.10.

. Is the conclusion affected by whether the significance level is 0.10 or 0.01​?

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