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    I got 2root5 for part ii.) but I need some help with i.) and especially iii.)

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    All help would be much appreciated
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    (Original post by TwiMaster)
    I got 2root5 for part ii.) but I need some help with i.) and especially iii.)

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    All help would be much appreciated
    For part (i) you just use the standard formulae

    \displaystyle E[\lambda X + \mu Y] = \lambda E[X] + \mu E[Y]

    \displaystyle V[\lambda X + \mu Y] = \lambda^2 V[X] + \mu^2 V[Y]

    for scalar  \lambda, \mu and X & Y independent.

    Part (ii) you have already. Part (iii) follows immediately from Chebychev by substituting in \bar_{X} and the corresponding standard deviation.
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    (Original post by Gregorius)
    For part (i) you just use the standard formulae

    \displaystyle E[\lambda X + \mu Y] = \lambda E[X] + \mu E[Y]

    \displaystyle V[\lambda X + \mu Y] = \lambda^2 V[X] + \mu^2 V[Y]

    for scalar  \lambda, \mu and X & Y independent.

    Part (ii) you have already. Part (iii) follows immediately from Chebychev by substituting in \bar_{X} and the corresponding standard deviation.

    Thank you very much!
 
 
 

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