A food processing plant packs cereal into boxes with a targeted mean mass of 500 g.
A consumer protection agency claims that the boxes are being underfilled on average.
To investigate, they weigh a sample of boxes and find the following:
n=250∑x=124625∑x2=62145000 n = 250 \quad \sum x = 124625 \quad \sum x^2 = 62145000 n=250∑x=124625∑x2=62145000Find the mean and standard deviation of the sample.
Carry out a hypothesis test to test the agency'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.