Skip to content

Course home

2.5 Statistical Hypothesis Testing

2.5 Statistical Hypothesis Testing

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177
Question 111

A factory produces metal rods with a target mean length of 12 cm. A quality control manager suspects the mean length has decreased and selects a random sample of 8 rods to test this claim. The lengths, in cm, are denoted by xxx and the following summary statistics were obtained:

∑x=94.4,∑x2=1114.2 \sum x = 94.4, \quad \sum x^2 = 1114.2 ∑x=94.4,∑x2=1114.2

Stating your hypotheses clearly, test at the 5% level of significance whether there is evidence that the mean length of the rods is less than 12 cm. You may assume that the lengths of the rods follow a normal distribution.

[7]
Markscheme

2.5 Statistical Hypothesis Testing Questions

  1. A Level
  2. /Maths
  3. /2.5 Statistical Hypothesis Testing

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.

Question bank