#### cabrown085

##### New Member

The probability density function seems to be a constant in most cases. As I found on Quora:

*A probability density function answers the question: "How common are samples at exactly this value?"*I understand that the PDF in a continuous distribution would be equal to 0.

It seems generally that the cumulative distribution function is the more useful equation for solving equations. In total, the max value of the function has to equal to 100% or 1. It looks at the cumulative nature of a variable, that it takes on a value equal to or less than the specific value.

My first question is where would you use the PDF in any instance but finding the CDF?

Finally, how do you take the inverse cumulative distribution function of a cumulative distribution function. In the example: F(x)=x^2/25, the inverse seems to F^-1=5x^(1/2).

I'm not especially familiar with taking the inverse of a function, so any tips would be appreciated.