Question 19.16 Test the null hypothesis at the .01 level of significance that the distribution of blood types for college students complies with the proportions described in the blood bank bulletin, namely, .44 for O, .41 for A, .10 for B, and .05 for AB. Now, however, assume that the results are available for a random sample of only 60 students. The results are as follows: 27 for O, 26 for A, 4 for B, and 3 for AB.

NOTE: The expected frequency for AB, (.05)(60) = 3, is less than 5, the smallest permissible expected frequency. generate sufficiently large expected frequency by combining B and AB blood types.

Table of Observed and Expected Counts

Blood types : O A B and AB

observed count: 27 26 7

Expected Count: 0.44(60) = 26.4 0.41(60) = 24.6 0.15(60) = 9

Research problem:

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Conclusion / interpretation: