a professor gives a test, the mean is 76 and standard deviation is 6 point. what...

Question

Question

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

Answer 1

Answer #1

P[X<91]

=P[Z<2.5]

=0.9938....................by using Z table.

Therefore, 99.38 % if the cut off mark is 91

Answer 2

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