A simple random sample of size n = 40 is drawn from a population. The sample mean is found to be x = 120.8 and the sample standard deviation is found to be s = 12.8. Construct a 99% confidence interval for the population mean. The lower bound is (Round to two decimal places as needed.) A Clear all Check answer View an example 79°F 11:36 PM 6/17/2022 O Bi Help me solve this Type here to search a Get more help. O

Use technology to construct the confidence intervals for the population variance o? and the population standard deviation o. Assume the sample is taken from a normally distributed population. c = 0.98, s2 = 11.56, n 27 The confidence interval for the population variance is (Round to two decimal places as needed.) Help me solve this View an example Get more help. Check answer Clear all 63°F Clea II C

Experience of Taxi Drivers A taxi company claims that its drivers have an average of at least 12.4 years’ experience. In a study of 15 taxi drivers, the average experience was 11.2 years. The standard deviation was 2. At alpha = 0.10, is the number of years’ experience of the taxi drivers really less than the taxi company claimed? Please show how to solve using the formulas, thanks!

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If n=15n=15, ¯xx¯=43, and s=20s=20, construct a confidence interval at a 90% confidence level. Give your answers to one decimal place.  _____< μ < _____ Technology

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Find the left and right chi square values, then give the confidence interval. Sample Variance s 15.99 %3D Confidence Level c = 0.90 and Sample Size n = 13 and x %3D %3D At the 90 % level of confidence the population variance is between and (Round all answers to 3 decimal places)

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Test a claim that the mean amount of lead in the air in U.S. cities is less than 0.038 microgram per cubic meter. It was found that the mean amount of lead in the air for the random sample of 56 U.S. cities is 0.038 microgram per cubic meter and the standard deviation is 0.068 microgram per cubic meter. At alphaαequals=0.01​, can the claim be​ supported? Complete parts​ (a) through​ (e) below. Assume the population is normally distributed.   d) Decide whether to reject or fail to reject the null hypothesis.   ▼   Fail to reject Reject Upper H 0H0 because the standardized test statistic ▼   is is not in the rejection region. ​(e) Interpret the decision in the context of the original claim.   There ▼   is not is enough evidence at the nothing​% level of significance to ▼   reject support the claim that the mean amount of lead in the air in U.S. cities is ▼   equal greater than or equal less than or equal not equal greater than less than nothing…

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