- #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)2fx(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!