# Math Help - z-score question

1. ## z-score question

The picture is the answer to a problem with n=500, standard deviation of 0.0155 and mean of 0.14. Can any one teach me how to get P(Z>3.87) and where .0002 came from? Thanks in advance.

2. Originally Posted by loadup2

The picture is the answer to a problem with n=500, standard deviation of 0.0155 and mean of 0.14. Can any one teach me how to get P(Z>3.87) and where .0002 came from? Thanks in advance.
What were you doing in class when this was set/given? Or what was in the section of the book course where this occurred?

My guess you were doing something about the normal distribution.

If so you need to look up 3.87 in a table of the cumulative standard normal distribution and subtract that from 1, but that does not give the given answer.

CB