In order to ensure efficient usage of a server, it is necessary to estimate the mean number of concurrent users. According to the records, the average number of concurrent users at 185 randomly selected times is 31.2, with a standard deviation σ = 3.6 Construct a 95% confidence interval for the expectation of the number of concurrent users. (Round the answer to 4 decimals)
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- a sociologist found that in a sample of 45 retired men, the average number of jobs they had during theirlifetimes was 7.2. The population standard deviation is 2.3.Find the 90% confidence interval of the mean number of jobs. Round intermediate and final answers to one decimalplace.<h<A certain group of test subjects had pulse rates with a mean of 70.470.4 beats per minute and a standard deviation of 11.111.1 beats per minute. Use the range rule of thumb to identify the limits separating values that are significantly low or significantly high. Is a pulse rate of 52.652.6 beats per minute significantly low or significantly high? Significantly low values are nothing beats per minute or lower.A data set includes 31 body temperatures of healthy adult humans having a mean of 98.3°F and a standard deviation of 0.82°F. Using this sample information, a 99% confidence interval estimate of the mean body temperature is found to be (97.90° , 98.71°). What does this information suggest about the use of 98.6°F as the mean body temperature? A. Since the confidence interval does not include the mean body temperature of 98.6°F, the results suggests that the mean body temperature could not be 98.6°F. B. Since the confidence interval includes the mean body temperature of 98.6°F, the results suggests that the mean body temperature could be 98.6°F. C. Since the confidence interval includes the mean body temperature of 98.6°F, the results suggests that the mean body temperature could not be 98.6°F. D. Since the confidence interval does not include the mean body temperature of 98.6°F, the results suggests that the mean body temperature could be 98.6°F. Click to select your answer. ?