Crossing the origin twice
A simple symmetric random walk starts at 0 and takes steps of . What is the probability that it is at 0 both after 2 steps and after 4 steps? Give a decimal to four places.
Show hints (2)+
- Steps 1–2 and steps 3–4 are independent blocks; each must net to 0.
- ; multiply the two blocks.
Answer
Reveal answer →Final answer
0.25
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Asked at: Probability & Market-Making, Timed Mental-Math & Sequences