Question
Let $X$ be a random variable such that $P(X \leq 0)=0$ and let $\mu=E(X)$ exist. Show that $P(X \geq 2 \mu) \leq \frac{1}{2}$.
Step 1
Step 1: First, we recall Markov's inequality, which states that for a non-negative random variable $X$ and any positive constant $a$, we have $P(X \geq a) \leq \frac{E(X)}{a}$. Show more…
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Key Concepts
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Transcript
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