Your manager who just read an abridged version of a statisti

Your manager, who just read an abridged version of a statistics book, wants you to test hypotheses for the difference in two population means. The sample sizes for each are 23.

Solution

if the population standard deviations of the two samples are given then perform Z test. If population standard deviations not given then since sample sizes less than 30 perform t test.

Since nothing is said about population standard deviation, assuming pop. S.d. is not given The test to be performed is t test. Not Z test.If the population standard deviations of the two samples are given then perform Ztest even when the samples are small.