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 $μ\mu$ g/L and standard deviation $σ\sigma$ g/L. A random sample of 12 batches is analysed. For this sample, the calculated mean concentration is $yˉ=216.5\bar{y} = 216.5$ and the unbiased estimate of the population variance is $s^2 = 58.5$ .

Test, at the 5% level of significance, whether or not $σ\sigma$ is greater than 5.5. State your hypotheses clearly.

Test, at the 5% level of significance, whether or not $μ\mu$ is greater than 212.0.

State an assumption about the distribution of catalyst concentrations that is necessary for these tests to be valid.

Test, at the 5% level of significance, whether or not $σ\sigma$ is greater than 5.5. State your hypotheses clearly.

Test, at the 5% level of significance, whether or not $μ\mu$ is greater than 212.0.

State an assumption about the distribution of catalyst concentrations that is necessary for these tests to be valid.

2.5.8 Hypothesis test for a single mean (A-level only)

Question 14

Markscheme

2.5.8 Hypothesis test for a single mean (A-level only)

Question 14

Markscheme

2.5.8 Hypothesis test for a single mean (A-level only)

Question 14

2.5.8 Hypothesis test for a single mean (A-level only) Questions

2.5.8 Hypothesis test for a single mean (A-level only)

Question 14

2.5.8 Hypothesis test for a single mean (A-level only) Questions