AppliedNumeric answer
A symmetric random walk starts at and stops the first time it reaches or . What is the probability it stops at ?
Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.
The worked solution is in Premium
The answer, the full working and the one idea to take away – for this and all 1,322 questions in the bank. Answer it in practice and your working is marked, with a known mistake named when you make one.
Learn the method
Reported in interviews at
More probability questions
- The gambler with an edge, part 1 of 3Foundation
- You have $10 and your opponent has $90.Applied
- You start with $10 against an opponent with $90, flipping a fair coin for $1.Applied
- How many flips of a fair coin are needed, on average, to see three heads in a row?Applied
- The gambler with an edge, part 2 of 3Applied
- Your opponent has $2 and you have $1.Advanced