Samples come from a normal distribution

Reference no: EM13963874

The following data give SAT mean scores for math by state for 1989 and 1999 for 20 randomly selected states (source: The World Almanac and Book of Facts 2000).

State	1989	1999
Arizona	523	525
Connecticut	498	509
Alabama	539	555
Indiana	487	498
Kansas	561	576
Oregon	509	525
Nebraska	560	571
New York	496	502
Virginia	507	499
Washington	515	526
Illinois	539	585
North Carolina	469	493
Georgia	475	482
Nevada	512	517
Ohio	520	568
New Hampshire	510	518

Assuming that the samples come from a normal distribution:

(a) Test that the mean SAT score for math in 1999 is greater than that in 1989 at α = 0.05. Assume the variances are equal.

(b) Test for the equality of the variances at α = 0.05.

Reference no: EM13963874

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