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.
Practise Edexcel A Level Maths The Normal Distribution with exam-style questions for A Level Maths. 100 questions covering The Normal Distribution, Finding Probabilities for Normal Distributions, The Inverse Normal Distribution Function, The Standard Normal Distribution, Finding the mean and standard deviation, Approximating a Binomial Distribution, and Hypothesis Testing with the Normal Distribution, 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.