Worked Example 3

Worked Example 3

TGM Original Questions
Free

Given that \(E\left( X \right)=3\), \(\mathrm{Var}\left( X \right)=4\), \(\mathrm{E}\left( Y \right)=-2\)and \(\mathrm{Var}\left( Y \right)=7\) . Find the expectation and variance of

  1. \(3X+2Y\)
  2. \(2X-3Y\)
  3. \({{X}_{1}}+{{X}_{2}}-{{Y}_{1}}-{{Y}_{2}}-{{Y}_{3}}\)

Video Solution:

Default solution

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Answer:(i) \(E = 5\), \(\text{Var} = 64\); (ii) \(E = 12\), \(\text{Var} = 79\); (iii) \(E = 12\), \(\text{Var} = 29\)

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