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2.5.3 Hypothesis test for a Normal mean (A-level only)

2.5.3 Hypothesis test for a Normal mean (A-level only)

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Question 17

A safety engineer tests the breaking strength of steel cables. The manufacturer claims the cables have a mean breaking strength of 80 kN. The engineer suspects the cables are weaker than claimed. Data from 200 cables are summarized below:

n=200∑x=15940∑x2=1271162 n = 200 \quad \sum x = 15940 \quad \sum x^2 = 1271162 n=200∑x=15940∑x2=1271162
a.

Find the mean and standard deviation of the sample.

[3]
b.

Carry out a hypothesis test to test the engineer's suspicion at the 1% significance level. State your assumptions clearly.

[5]
Markscheme

2.5.3 Hypothesis test for a Normal mean (A-level only) Questions

  1. A Level
  2. /Maths
  3. /2.5.3 Hypothesis test for a Normal mean (A-level only)

130 exam-style questions on AQA A Level Maths 2.5.3 Hypothesis test for a Normal mean (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

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