How do I find standard deviation and variance from the casino game “roulette?” (For my Prob. & Stats class)?
Question by Drumminnerd: How do I find standard deviation and variance from the casino game “roulette?” (For my Prob. & Stats class)?
Best answer:
Answer by Merlyn
This question is to vague to give specifics. What you’ll need to do is define your random variable X and then you’ll be able to find a mean and variance.
For example:
X = winning on black, i.e., you bet on black, X is the amount you win. This will be subject to how much you bet and could win.
X = winning on “0″
X = winning on “00″
After you define the random variable you can use the following to find the mean, variance and standard deviation.
for any discrete random variable the expectation is:
E(X) = μ = ∑x * P(X = x)
the variance of a discrete random variable is:
Var(X) = σ² = ∑(x – μ)² * P(X = x) = {∑x² * P(X = x) }- μ²
the standard deviation is just the square root of the variance.
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Tags: casino, Class, deviation, Find, from, game, Prob., Roulette, Standard, Stats, variance
