412.Walking the Circle to Zero
★★★random walksCh. 5 — Multivariate Distributions and Moments444+ Problems in Probability
You stand on a circle of 100 points labeled –, starting at point 1. Each turn you move one step left or right with equal probability. What is the expected number of steps to reach point 0?
Sign in to submit an answer and track it toward your stats.
Sign inHint
For a symmetric walk on a cycle of points, the expected hitting time of 0 from distance has a famously clean closed form.
Want timed drills, mental math, and a market-making game too? Try the full practice suite →