# Help with Probably Density Function Question

#### student93

1. The problem statement, all variables and given/known data

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2. Relevant equations

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3. The attempt at a solution

I can solve the integral since I know P(X) = ∫f(x)dx=1 from a to b, however I can't figure out how to derive the function from the given graph.

Also the answer is D. 3/4.

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#### SteamKing

Staff Emeritus
Homework Helper
1. The problem statement, all variables and given/known data

Problem is attached in this post

2. Relevant equations

Problem is attached in this post

3. The attempt at a solution

I can solve the integral since I know P(X) = ∫f(x)dx=1 from a to b, however I can't figure out how to derive the function from the given graph.

Also the answer is D. 3/4.
The PDF is either 0 or straight lines. Why is it so difficult to construct the PDF in a piecewise fashion?

#### student93

I'm not familiar with that method, could you please elaborate and/or post a link that explains how to construct a probability density function via the piecewise method?

#### ehild

Homework Helper
The probability density function is given graphically. How do you get graphically the probability from the probability density function ?

ehild

#### HallsofIvy

Do you not know how to find the function that has a straight line as its graph?

#### LCKurtz

Homework Helper
Gold Member
I second ehild's hint. You don't even need the equations.

#### jbunniii

Homework Helper
Gold Member
oops, never mind, misread

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