A manufacturer of energy drinks claims that each can contains a mean caffeine content of 160 mg.
A nutritionist suspects that the caffeine content is actually lower than 160 mg.
The nutritionist tests a sample and records the following summary statistics:
n=150∑x=23745∑x2=3776363 n = 150 \quad \sum x = 23745 \quad \sum x^2 = 3776363 n=150∑x=23745∑x2=3776363Find the mean and standard deviation of the sample.
Carry out a hypothesis test to test the nutritionist's claim at the 1% significance level. State your assumptions clearly.
316 exam-style questions on OCR A Level Maths 2.5 Statistical Hypothesis Testing, covering 2.5.1 The language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, 2.5.3 Inference and significance level, 2.5.4 Sample mean as a random variable (A-level only), 2.5.5 Hypothesis test for the mean of a normal distribution (A-level only), 2.5.6 Pearson's product-moment correlation coefficient, and 2.5.7 Hypothesis test using Pearson's coefficient (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.