Question

03)

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 89 80 58 100 62 87 69 89 82 83 57 80 74 102 62 Past 88 88 93 94 65 84 86 92 88 91 91 91 Let u, be the recent times and let u be the past times. What are the null and alternative hypotheses? О В. Н , 3P H 2 O A. Ho H2 H 2 O D. Ho H 2 H ОС. На H 2 Calculate the test statistic. (Round to two decimal places as needed.) Find the P-value P-value (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. the significance level. There sufficient evidence that the mean time interval has changed. Ho because the P-value is Is the conclusion affected by whether the significance level is 0.10 or 0.01? O A. Yes, the conclusion is affected by the significance level because Ho is rejected when the significance level is 0.01 but is not rejected when the significance level is 0.10. O B. No, the conclusion is not affected by the significance level because Ho is not rejected regardless of whether significance level of 0.10 or 0.01 is used. O C. No, the conclusion is not affected by the significance level because Ho is rejected O D. Yes, the conclusion is affected by the significance level because H is rejected when the significance level is 0.10 but is not rejected when the significance level is 0.01 icance level of 0.10 or 0.01 is used. gardless of whether a si
Answer Option:

(fail to reject. Reject) Ho because the P-value is (greater than. Less than or equal to) the significance level. There (is not. Is) sufficient evidence that the mean time interval has charged

Answer 1

solution Here Hool, = M2 is Hill, I us Given n=17, X= 78-9, 8, = 13.7 N2 =12, X2 = 87.58, B2=7.69 4-2 78-9-87.58 Text statistic t = 2 -- (7.692 ] - 2.172 (13-7 12 27 d-f=25, P-value=oooul here P-value coil Reject Ho. Because the P-value is less than the significance lovel. There is sufficient evidence that the mean the mean time interval has changed. - here when a=0.01, P-value >a, so do not reject to → Yes the conclusion is effected by the significance level because to is rejected when the Lao1 but is not rejected when d=0.01. option (D)