Statistics practice problem, have no clue, please help me out here, thanks so much?

Question

A human resources manager is assessing the popularity of the current compensation plan. The manager collects two samples of 50 employees each from two different divisions in the company. In the first sample, 40 individuals indicated that they are in favor of the current plan. In the second sample, only 30 individuals indicated that they are in favor of the current plan. Conduct a hypothesis test at a 5 percent level of significance to determine whether the proportion in favor of the plan is significantly different between the two samples.

Answer 1

This will be a 2-proportion z-test, because you're comparing the percentage of one sample that favors the plan with the percentage in the second sample in favor. Exactly how you do the test depends on how you've done things in your class. Most stats classes these days are technology based. If so, you'd likely go to a TI-83 or similar calculator, go to "STAT", choose "TESTS" and find "2-Prop-ZTest". x1=40, n1=50, x2=30, and n2=50. You will then either compare the expected error value "P" generated by the calculator with the 5% you are given or alternately look up the value of z that corresponds to 5% error in a table and see if the value of z calculated by the calculator is more or less than that.

If your class does not use graphing calculator methods, you will instead look up the formula for a 2-proportion z-test. You'll calculate "z" using that formula and compare it with the table value.

In general, a result is significant (reject the null hypothesis) if the value you calculate for z is more than the critical value from the table. (If you are using p-value methods, the opposite is true, the p-value on your calculator should be less than the value given in the problem.)