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 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 wit 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.)

A college student is interested in investigating the claim that students who graduate with a master’s degree earn higher salaries, on average, than those who finish with a bachelor’s degree. She surveys, at random, 49 recent graduates who completed their master’s degrees, and finds that their mean salary is $⁢37,400 per year. The standard deviation of annual salaries for the population of recent graduates who have master’s degrees is known to be $⁢2400. She also surveys, at random, 37 recent graduates who completed their bachelor’s degrees, and finds that their mean salary is $⁢36,700 per year. The standard deviation of annual salaries for the population of recent graduates with only bachelor’s degrees is known to be $⁢1900. Test the claim at the 0.05 level of significance. Let recent graduates with a master's degree be Population 1 and let recent graduates with a bachelor's degree be Population 2.   Step 2 of 3 :   Compute the value of the test statistic. Round your answer to…

A college student is interested in investigating the claim that students who graduate with a master’s degree earn higher salaries, on average, than those who finish with a bachelor’s degree. She surveys, at random, 49 recent graduates who completed their master’s degrees, and finds that their mean salary is $⁢31,100 per year. The standard deviation of annual salaries for the population of recent graduates who have master’s degrees is known to be $⁢1000. She also surveys, at random, 38 recent graduates who completed their bachelor’s degrees, and finds that their mean salary is $⁢30,300 per year. The standard deviation of annual salaries for the population of recent graduates with only bachelor’s degrees is known to be $⁢2100. Test the claim at the 0.05 level of significance. Let recent graduates with a master's degree be Population 1 and let recent graduates with a bachelor's degree be Population 2. Step 3 of 3 :   Draw a conclusion and interpret the decision.

A college student is interested in investigating the claim that students who graduate with a master’s degree earn higher salaries, on average, than those who finish with a bachelor’s degree. She surveys, at random, 49 recent graduates who completed their master’s degrees, and finds that their mean salary is $⁢31,100 per year. The standard deviation of annual salaries for the population of recent graduates who have master’s degrees is known to be $⁢1000. She also surveys, at random, 38 recent graduates who completed their bachelor’s degrees, and finds that their mean salary is $⁢30,300 per year. The standard deviation of annual salaries for the population of recent graduates with only bachelor’s degrees is known to be $⁢2100. Test the claim at the 0.05 level of significance. Let recent graduates with a master's degree be Population 1 and let recent graduates with a bachelor's degree be Population 2. Step 2 of 3 :   Compute the value of the test statistic. Round your answer to two…