Worked Example 2

Worked Example 2

TGM Original Questions
Free

Given that the random variables \(X\) and \(Y\) have distributions \(N(60, 25)\) and \(N(54, 64)\) respectively, and that \(\bar{X}\) and \(\bar{Y}\) denotes the means of \(7\) independent observations of \(X\) and \(11\) independent observations of \(Y\) respectively.

State the sampling distributions of

  1. \(\bar{X}-\bar{Y}\)
  2. \(2\bar{X}+5\bar{Y}\)
  3. \(\frac{{{X}{1}}+{{X}{2}}+{{X}{3}}-{{Y}{1}}-{{Y}{2}}-…-{{Y}{5}}}{8}\)

Video Solution:

Default solution

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Answer:(i) \(\bar{X} - \bar{Y} \sim N(6, 9.39)\); (ii) \(W \sim N(390, 160)\); (iii) \(Q \sim N(-11.25, 6.17)\)

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