The shelf life of a specific type of fresh bread is normally distributed.
14% of the loaves spoil in fewer than 3 days. 18% of the loaves stay fresh for longer than 7 days.
Find the mean and standard deviation of the shelf life of the bread.
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.