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...
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