Markov with a floor

MediumStatistics~4m

A random variable is always at least $1$ (it never dips below $1$ ) and has mean $5$ . Using Markov's inequality as tightly as possible, what upper bound can you give for $P(X \ge 13)$ ? (to 3 decimals)

Show hints (2)+

X >= 1, not X >= 0 - shift to Y = X - 1 so Markov applies to a genuinely non-negative variable.
E[Y] = 4 and the event becomes Y >= 12, giving 4/12.

Answer

Reveal answer →

0.333 (± 0.002)

Create a free account to see the full worked solution and track your progress.

Create a free account

Interview format: Market Maker, Hedge Fund Quant

Markov with a floor

Answer

Related questions