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.
48 exam-style questions on Edexcel A Level Maths 3.5 Finding the mean and standard deviation. Each one has a worked solution and a mark scheme showing where the marks go.