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.
390 exam-style questions on AQA A Level Maths 2.4 N: Statistical distributions, covering 2.4.1 Discrete distributions and the binomial, 2.4.2 The Normal distribution (A-level only), and 2.4.3 Selecting an appropriate distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.