- #1

Samwise_geegee

- 6

- 0

## Homework Statement

For a certain random variable X, P(X≤500)=.5 and P(X>650)=.0227, find σ.

## Homework Equations

μ=expected value=mean

Variance=∫(X-μ)

^{2}fx(X)dx evaluated from -∞ to ∞

σ=√Variance

## The Attempt at a Solution

I'm not sure what the relationships between the standard deviation and the probabilities given are.

My only guess is that P(X≤500)=.5 also fits the definition for the median of this function but I'm not sure where the median fits into the standard deviation either. Any help is appreciated!