The heights of a specific species of plant are normally distributed. 20% of the plants are shorter than 15 cm. 10% of the plants are taller than 25 cm.
Find the mean and standard deviation of the heights of the plants.
147 exam-style questions on OCR A Level Maths 2.4.6 Probabilities using the normal distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.