https://padlet.com/dolphineho/27cifzig4dtyj859 en-us 2020-12-03 12:46:09 UTC 2020-12-04 01:06:56 UTC hello@padlet.com dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983430792 An entrepreneur is considering the purchase of a coin-operated laundry. The present owner claims that over the past 5 years, the average daily revenue was $675 with a standard deviation of $75. A sample of 30 days reveals a daily average revenue of $625. If you were to test the null hypothesis that the daily average revenue was $675, which test would you use?]]> 2020-12-03 12:46:43 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983430792 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983433635 A manager of the credit department for an oil company would like to determine whether the average monthly balance of credit card holders is equal to $75. An auditor selects a random sample of 100 accounts and finds that the average owed is $83.40 with a sample standard deviation of $23.65. If you wanted to test whether the auditor should conclude that there is evidence that the average balance is different from $75, which test would you use?]]> 2020-12-03 12:47:54 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983433635 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983449985 The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club. She would now like to determine whether or not the mean age of her customers is over 30. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. The appropriate hypotheses to test are:]]> 2020-12-03 12:53:57 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983449985 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983460582 The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club. She would now like to determine whether or not the mean age of her customers is over 30 with a standard deviation of 5 years. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. Suppose she found that the sample mean was 30.45 years and the sample . What is the p value associated with the test statistic?]]> 2020-12-03 12:57:56 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983460582 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983471946 The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club. She would now like to determine whether or not the mean age of her customers is over 30. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. The appropriate hypotheses to test are:]]> 2020-12-03 13:02:19 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983471946 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983476909 56. A manager of the credit department for an oil company would like to determine whether the average monthly balance of credit card holders is equal to $75. An auditor selects a random sample of 100 accounts and finds that the average owed is $83.40 with a sample standard deviation of $23.65. If you wanted to test whether the auditor should conclude that there is evidence that the average balance is different from $75, which test would you use?]]> 2020-12-03 13:04:17 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/983476909 190477401 https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986165606 We would use one sample T test. This is because the random sample standard deviation is known and the population standard deviation is unknown.

]]> 2020-12-04 00:35:29 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986165606 190477401 https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986172442 P(X>30)=P(Z>1.423)= 0.5 - 0.4222 = 0.0778]]> 2020-12-04 00:38:36 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986172442 https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986173530 Use t test]]> 2020-12-04 00:39:06 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986173530 190477401 https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986185581 H0: Average age of customers is equal to 30 years old (mu=30)
H1: Average age of customers is more than 30 years old (mu>30)]]> 2020-12-04 00:44:27 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986185581 190477401 https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986190401 One sample Z test.]]> 2020-12-04 00:46:37 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986190401 dolphineho https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986229067 Z value = X-bar - mu / (sigma / sqrtn)
= 30.45 - 30 / (5/sqrt250)
= 1.42
Go to Z table, it will give you 0.4222.]]> 2020-12-04 01:04:13 UTC https://padlet.com/dolphineho/27cifzig4dtyj859/wish/986229067