## Question 670:

1## Answer:

No answer provided yet.The test-statistic z* is found as the difference between the sample mean and test mean = 147.8-150 = -2.2. Next, divide the difference by the standard error of the difference (SE). SE is the standard deviation divided by the square root of the sample size = 4.5/SQRT(15) = 1.1618. This would make the test statistic = -2.2/1.1618 = -1.893.