(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Problem description:

A variable X has expected value 0.002 in meters. Consider X - 0.002, scale to millimeter, and we get Y.

Tasks:

a) Express Y as a function of X

b) Relate the probability distributions F_{X}and F_{Y}

c) Relate the probability density functions f_{X}and f_{Y}

2. Relevant equations

[tex] F(x) = \operatorname P ( X \leq x ) = \int_{-\infty}^x f(t) \, \mathrm{d}t [/tex]

[tex] \int_{-\infty}^{\infty} f(x) \, \mathrm{d}x = 1[/tex]

[tex] f(x) = F'(x) \geq 0 [/tex]

3. The attempt at a solution

a) Y = 1000X - 2

(I think)

b) I have no clue. I mean, I could make a wild guess, but I don't see any reason to.

c) I suppose we get f_{X}and f_{Y}by differentiating F_{X}and F_{Y}... somehow.

I also don't really know what it means to "relate" these things. Is it to express the one in terms of the other, so that for example if a*b = c then relating a to b I either say that a = c/b or that b = c/a? Or what?

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# Homework Help: Relating probability distributions huh?

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