The length of time for long-distance phone calls has been found to be normally distributed, with a mean of 20.8 minutes and a standard deviation of 6.7 minutes. In a randomly selected sample of 68 calls, what is the sample average call time below which 10% of sample average call times will be shorter? (2 decimal places)

Question 7A statistical analysis of 2,000 long-distance telephone calls made from the headquarters of theBricks and Clicks Computer Corporation indicates that the length of these calls is normallydistributed, with 𝜇 = 300 seconds and 𝜎 = 50 seconds. (4 marks)(a) What is the probability that a call lasted less than 210 seconds?(b) What is the probability that a call lasted between 210 and 320 seconds?(c) What is the probability that a call lasted between 100 and 210 seconds?(d) 10% of all calls will last less than how many seconds?

The manager of a computer shop is recording the time taken for customers to decide of which computer and accessories they buy from the time they enter the store. From the previous data, it is known that the average ‘decision’ time was 45 minutes. The manager assumes a normally distributed population with a standard deviation of 10 minutesa)  What is the probability that a customer will take more than 60 minutes?

QUESTION 5A study was conducted to determine the duration of a typical consultation in an urban medical practice.  The results showed that the length of a consultation could be closely approximated by a normal distribution with a mean of 12.4 minutes and a variance of 9.75 minutes2.a)  Find the probability that a consultation would last less than 9 minutes.  (3 decimal places)b) How many of the individual patients visiting the medical centre will have a consultation time of less than 9 minutes if there are 522 individual patient consultations on a given day? Use your rounded answer, with 3 decimal places, from part a.    (Round your answer to the nearest whole number)

Dave drives to work each morning at about the same time. His commute time is normally distributed with a mean of 50 minutes and a standard deviation of 6 minutes.  What percentage of the time will his commute time be greater than 58 minutes?

un times at a local marathon are known to follow a left-skewed distribution with a mean of 256 minutes and a standard deviation of 100 minutes. If we select a random sample of 46 people, what is the probability that the average run time of this sample will be between 231 minutes and 264 minutes?Give your answer to four decimal places. If the question cannot be answered with the information given, enter -1 as your answer.