An article in American Demographics claims that more than twice as many shoppers are out shopping on the weekends thanduring the week. Not only that, such shoppers also spend more money on their purchases on Saturdays and Sundays!Suppose that the amount of money spent at shopping centers between 4 p.m. and 6 p.m. on Sundays has a normaldistribution with mean $180 and with a standard deviation of $20. A shopper is randomly selected on a Sunday between4 p.m. and 6 p.m. and asked about his spending patterns.In USE SALT(a) What is the probability that he has spent more than $190 at the mall? (Round your answer to four decimal places.)(b) What is the probability that he has spent between $190 and $205 at the mall? (Round your answer to four decimalplaces.)(c) If two shoppers are randomly selected, what is the probability that both shoppers have spent more than $205 at themall? (Round your answer to four decimal places.)You may need to use the appropriate appendix table to answer this question.

Let X be the random variable from normal distribution with mean (μ) = $180 and standard deviation…

Answered: An article in American Demographics…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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An article in American Demographics claims that more than twice as many shoppers are out shopping on the weekends than during the week. Not only that, such shoppers also spend more money on their purchases on Saturdays and Sundays! Suppose that the amount of money spent at shopping centers between 4 p.m. and 6 p.m. on Sundays has a normal distribution with mean $195 and with a standard deviation of $20. A shopper is randomly selected on a Sunday between 4 p.m. and 6 p.m. and asked about his spending patterns. What is the probability that he has spent between $205 and $225 at the mall? (Round your answer to four decimal places.)
Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 8 million dollars and a standard deviation of 1.3 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 10% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place. 00 0 million dollars X S ? Check acer Q tab esc ! 1 9. a @ 2 W →> S #m 3 X e C d $ LAS 4 C r % 5 f t > < 6 g y & JX b 7 h C n K1300
An article in American Demographics claims that more than twice as many shoppers are out shopping on the weekends than during the week. Not only that, such shoppers also spend more money on their purchases on Saturdays and Sundays! Suppose that the amount of money spent at shopping centers between 4 p.m. and 6 p.m. on Sundays has a normal distribution with mean $170 and with a standard deviation of $20. A shopper is randomly selected on a Sunday between 4 p.m. and 6 p.m. and asked about his spending patterns. A USE SALT (a) What is the probability that he has spent more than $180 at the mall? (Round your answer to four decimal places.) (b) What is the probability that he has spent between $180 and $200 at the mall? (Round your answer to four decimal places.) (c) If two shoppers are randomly selected, what is the probability that both shoppers have spent more than $200 at the mall? (Round your answer to four decimal places.) You may need to use the appropriate appendix table to answer…

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