A precision engineering plant fills high-pressure gas cylinders to a volume, V V\,V mL, which follows a normal distribution N(μ,122)N(\mu, 12^2)N(μ,122). To monitor the consistency of the filling process, a random sample of n n\,n cylinders is selected and tested at the 1% level of significance using the following hypotheses:
H0:μ=1500andH1:μ<1500 H_0 : \mu = 1500 \quad \text{and} \quad H_1 : \mu < 1500 H0:μ=1500andH1:μ<1500Find, in terms of nnn, the critical region of the test.
The probability of a Type II error, when the true mean is μ=1490\mu = 1490μ=1490, is less than 0.05.
Find the minimum value of nnn.
Practise Edexcel A Level Maths The Normal Distribution with exam-style questions for A Level Maths. 439 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.
