The scores of students in a physics olympiad, SSS, follow a normal distribution. Data shows that 10% of students scored less than 45 marks, and 5% of students scored more than 85 marks.
Calculate the mean score and the standard deviation of the scores.
228 exam-style questions on CCEA A Level Maths 4.5.1 Statistical distributions (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.