A bio-engineering lab measures the concentration of a specific catalyst in batches of synthetic fuel. The concentration levels follow a normal distribution with mean μ\muμ g/L and standard deviation σ\sigmaσ g/L. A random sample of 12 batches is analysed. For this sample, the calculated mean concentration is yˉ=216.5\bar{y} = 216.5yˉ=216.5 and the unbiased estimate of the population variance is s2=58.5s^2 = 58.5s2=58.5.
Test, at the 5% level of significance, whether or not σ\sigmaσ is greater than 5.5. State your hypotheses clearly.
Test, at the 5% level of significance, whether or not μ\muμ is greater than 212.0.
State an assumption about the distribution of catalyst concentrations that is necessary for these tests to be valid.
Practise Edexcel A Level Maths Hypothesis Testing with the Normal Distribution with exam-style questions for A Level Maths. 132 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.
