Question

Most graduate business schools require applicants to take the gmat. scores on this test are approximately normally distributed with a mean of 545 points and a standard deviation of 100 points. what score do you need to be in the top 5% (approximately the scores needed for top schools)?

Answer 1

We are looking for the probability :

`P(X > n)=0.05`
Transform the law to standard normal like this:

`P((X-545)/(100)> (n-545)/(100))=0.05`
The above formula is equivalent to this one:

`P((X-545)/(100)< (n-545)/(100))=0.95`
From normal law table, we read the value of
`(X-545)/(100)`.

`(X-545)/(100)=1.7`
Solving the above equation for the score n:

`X-545=170`

`X=715`, it is the score we are looking for.