The viscosity of a specific liquid polymer, VVV, is known to be normally distributed with a mean of 1420 mPa·s and a standard deviation of 115 mPa·s. A quality control engineer takes a random sample of 24 independent batches to monitor the stability of the production line. Determine the probability that the mean viscosity of this sample, Vˉ\bar{V}Vˉ, is less than 1385 mPa·s.
Practise Edexcel A Level Maths Finding Probabilities for Normal Distributions with exam-style questions for A Level Maths. 80 questions, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.