# Probability Distribution Function Help

• Apr 6th 2011, 07:13 AM
jscfc
Probability Distribution Function Help
Given the probability distribution function:

Attachment 21378

Determine the:
1. Probability density function.
2. The mean.
3. The median.
Hello,
I am really struggling with this subject area, this is an example I have found, would someone be able to go through a solution so I can begin to understand it a bit more.
Thanks.
• Apr 6th 2011, 07:30 AM
TheEmptySet
Quote:

Originally Posted by jscfc
Given the probability distribution function:

Attachment 21378

Determine the:
1. Probability density function.
2. The mean.
3. The median.
Hello,
I am really struggling with this subject area, this is an example I have found, would someone be able to go through a solution so I can begin to understand it a bit more.
Thanks.

First you have a typo in your problem.
Second we are not mind readers so please tell us that the function is the Cumulative distribution function
Cumulative distribution function - Wikipedia, the free encyclopedia

Your book or the above wiki will tell you that the CDF is the integral of the PDF

$\displaystyle \displaystyle F(X)=\int_{-\infty}^{x}f(t)dt$

So to undo an integral we will use the fundamental theorem of calculus to take the derivative of $\displaystyle F(x)$

This will give $\displaystyle f(x)$ the PDF

This will answer the rest of you question.

Exponential distribution - Wikipedia, the free encyclopedia

If you get stuck please post some work so we can see where.