Question
An ant walks along the edges of a cube and moves to one of the three adjacent vertices with equal probability at each step. Find the expected number of steps needed for the ant to reach the vertex opposite of where it started.
medium Probability
Cubic Ant I
A release-checked medium problem for training Conditional Expectation, Geometric Probability, Markov Chains, Expected Value.
Practice focus
This Probability problem is tagged Conditional Expectation, Geometric Probability, Markov Chains, Expected Value. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.
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