I am trying to figure out what the top 1% of marks are for a set of past exams, where I only have the passing mark of 58% and the percentage of people who passed. 45%.

I want to use the normal distribution to estimate the grade achieved by the top 1% of students who passed. So assuming the student's marks are normally distributed and 45% of people scored 58/100 or more.

Is there a way to do this?