According to a Human Resources report, a worker in the industrial countries spends on average 419 minutes a day on the job. Suppose the standard deviation of time spent on the job is 27 minutes. a. If the distribution of time spent on the job is approximately bell shaped, between what two times would 68% of the figures be? b. Between what two times would the figures be 95%? c. Suppose a worker spent 400 minutes on the job. What would that worker’s z score be, and what would it tell the researcher?
Answer:
Mean timings = 419 mins and standerd deviation = 27 mins
68% of the figures is equal to mean +- sigma = so range is ( 419-27 , 419 +27) = ( 392, 446)
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