Let X denote the courtship time for a randomly selected female-male pair of mating scorpion flies (time from beginning of interaction until mating). Suppose the mean value of X is 120 min and the standard deviation of X is 110 min. a) Is it plausible that X is normally distributed? O No, courtship time cannot plausibly be normally distributed. Since X must be negative, realistically the interval μ ±30 should be entirely negative which is not true in this case. O Yes, courtship time is plausibly normally distributed since the mean of X is larger than 100. O No, courtship time cannot plausibly be normally distributed. Since X must be non-negative, realistically the interval μ ± 30 should be entirely non-negative which is not true in this case. O Yes, courtship time is plausibly normally distributed. Since X must be non-negative, realistically the interval μ ± 30 should be entirely non-negative which is true in this case. O Yes, courtship time is plausibly normally distributed. Since X must be negative, realistically the interval u ± 30 should be entirely negative which is true in this case.

arn.squ.edu.om/mod/quiz/attempt.php?attempt=1766808&cmid=8751228&page=D21 SYSTEM (ACADEMIC) s Statistics 1 || Spring21 Time left 0: Suppose a company produces lightbulbs with a mean lifetime of 1000 hours and a standard deviation of 50 hours. So, the z-score for a particular lightbulb that lasts for only 700 hours is a. 300 b. 6

Assume that females have pulse rates that are normally distributed with a mean of u = 73.0 beats per minute and a standard deviation of o = 12.5 beats per minute. Complete parts (a) through (c) below. .... a. If 1 adult female is randomly selected, find the probability that her pulse rate is less than 76 beats per minute, The probability is (Round to four decimal places as needed.) b. If 25 adult females are randomly selected, find the probability that they have pulse rates with a mean less than 76 beats per minute. The probability is (Round to four decimal places as needed.) c. Why can the normal distribution be used in part (b), even though the sample size does not exceed 30? O A. Since the distribution is of individuals, not sample means, the distribution is a normal distribution for any sample size. O B. Since the original population has a normal distribution, the distribution of sample means is a normal distribution for any sample size. OC. Since the mean pulse rate exceeds 30,…

Let X denote the courtship time for a randomly selected female-male pair of mating scorpion flies (time from the beginning of interaction until mating). Suppose the mean value of X is 120 min and the standard deviation of X is 110 min (suggested by data in the article "Should I Stay or Should I Go? Condition- and Status-Dependent Courtship Decisions in the Scorpion Fly Panorpa Cognate"t). In USE SALT (a) Is it plausible that X is normally distributed? O Yes, courtship time is plausibly normally distributed. Since X must be non-negative, realistically the interval µ ± 30 should be entirely non-negative which is true in this case. O No, courtship time cannot plausibly be normally distributed. Since X must be non-negative, realistically the interval u ± 30 should be entirely non-negative which is not true in this case. O Yes, courtship time is plausibly normally distributed. Since X must be negative, realistically the interval u ± 30 should be entirely negative which is true in this case.…