Question

The Graduate Management Admission Test (GMAT) is a test required for admission into many Master of Business Administration (MBA) programs. Total scores on the GMAT are normally distributed. The Graduate Management Admission Council, who administers the test, claims that the mean total score is 579. (Source: http://www.mba.com/.) Suppose a random sample of 8 students took the test, and their scores are given below.

699, 560, 414, 570, 521, 663, 727, 413

At the 0.05 level of significance, test the claim that the mean score is less than 579.

Set up the curve with the rejection region and critical value. State conclusion in a sentence.

Answer 1

First we need to find the mean and SD of data set. Following table shows the calculations:

	X	(X-mean)^2
	699	16416.01563
	560	118.265625
	414	24609.76563
	570	0.765625
	521	2487.515625
	663	8487.015625
	727	24375.01563
	413	24924.51563
Total	4567	101418.875

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Conclusion: There is no evidence to conclude that the mean score is less than 579.

Following is the curve:

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