Assume that the shrimps' weights are normally distributed.ANS:Mean = 1.4 Standard deviation = 0.611.The monthly earnings of computer programmers are normally distributed with a mean of $4,000. If only 1.7 percent of programmers have monthly incomes of less than $2,834, what is the value of the standard deviation of the monthly earnings of the computer programmers?ANS:$55012.A major department store has determined that its customers charge an average of $500 per month, witha standard deviation of $80. Assume the amounts of charges are normally distributed.a.What percentage of customers charges more than $380 per month?b.What percentage of customers charges less than $340 per month?c.What percentage of customers charges between $644 and $700 per month?ANS:a.93.32%b.2.28%c.2.97%13.The First National Mortgage Company has noted that 6% of its customers pay their mortgage payments after the due date.a.What is the probability that in a random sample of 150 customers 7 will be late on their payments?b.What is the probability that in a random sample of 150 customers at least 10 will be late on their payments?ANS:a.0.1066b.0.4325

14.The salaries of the employees of a corporation are normally distributed with a mean of $25,000 and a standard deviation of $5,000.a.What is the probability that a randomly selected employee will have a starting salary of at least $31,000?b.What percentage of employees has salaries of less than $12,200?c.What are the minimum and the maximum salaries of the middle 95% of the employees?d.If sixty-eight of the employees have incomes of at least $35,600, how many individuals are employed in the corporation?ANS:a.0.1151b.0.52%c.minimum = $15,200 maximum = $34,800d.4,00015.A manufacturing process produces items whose weights are normally distributed. It is known that 22.57% of all the items produced weigh between 100 grams up to the mean and 49.18% weigh from the mean up to 190 grams. Determine the mean and the standard deviation.ANS:standard deviation = 30 mean = 11316.The daily dinner bills in a local restaurant are normally distributed with a mean of $28 and a standard deviation of $6.a.What is the probability that a randomly selected bill will be at least $39.10?b.What percentage of the bills will be less than $16.90?c.What are the minimum and maximum of the middle 95% of the bills?d.If twelve of one day's bills had a value of at least $43.06, how many bills did the restaurant collect on that day?ANS:a.0.0322b.0.0322c.minimum = $16.24 maximum = $39.06d.2,00017.The price of a bond is uniformly distributed between $80 and $85.a.What is the probability that the bond price will be at least $83?b.What is the probability that the bond price will be between $81 to $90?c.Determine the expected price of the bond.d.Compute the standard deviation for the bond price.ANS:a.0.4b.0.8c.$82.50d.$1.4418.The price of a stock is uniformly distributed between $30 and $40.

a.What is the probability that the stock price will be more than $37?

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