a professor gives a test, the mean is 76 and standard deviation is 6 point. what is the percentage if the cut off mark is 91
P[X<91]
=P[Z<2.5]
=0.9938....................by using Z table.
Therefore, 99.38 % if the cut off mark is 91 |
a professor gives a test, the mean is 76 and standard deviation is 6 point. what...
Professor Blockhus gives two different statistics tests, but one test is harder than the other. Scores on test A are normally distributed with a mean score of 78 and a standard deviation of 6. Scores on test B are also normally distributed but with a mean score of 65 and a standard deviation of 9. If Erik scored an 79 on test B, what percent of the class scored below him? That is, what is his percentile on test B.
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A test has a mean of 81 and a Standard Deviation of 8. What percentage of cases falls above a score of 77? Below a score of 93?
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