The 100m race times an athlete records are normally distributed.
16% of the time the athlete is faster than 10 seconds.
23% of the time the athlete is slower than 11 seconds.
Find the mean and standard deviation of the times.
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.