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2 Statistics

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Question 269

A precision engineering plant fills high-pressure gas cylinders to a volume, V V\,V mL, which follows a normal distribution N(μ,122)N(\mu, 12^2)N(μ,122). To monitor the consistency of the filling process, a random sample of n n\,n cylinders is selected and tested at the 1% level of significance using the following hypotheses:

H0:μ=1500andH1:μ<1500 H_0 : \mu = 1500 \quad \text{and} \quad H_1 : \mu < 1500 H0​:μ=1500andH1​:μ<1500
a.

Find, in terms of nnn, the critical region of the test.

[3]
b.

The probability of a Type II error, when the true mean is μ=1490\mu = 1490μ=1490, is less than 0.05.

Find the minimum value of nnn.

[5]
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2 Statistics Questions

  1. A Level
  2. /Maths
  3. /2 Statistics

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