The grades on the last math exam had a mean of 72%. Assume the population of grades on math exams is known to be distributed normally, with a standard deviation of 5%. Approximately what percent of students earn a score between 72% and 87%?

49.9%
1%
50%
47.7%

Question

The grades on the last math exam had a mean of 72%. Assume the population of grades on math exams is known to be distributed normally, with a standard deviation of 5%. Approximately what percent of students earn a score between 72% and 87%?

 49.9%
 1%
 50%
 47.7%

anonymous · Answer

@pooja195 @nincompoop @ganeshie8

anonymous · Answer

basic stats problem...
need an idea of how much you understand first, so I'll ask a preliminary question....

How many standard deviations from 72 is 87? (remember, the standard deviation is 5)