medium   Probability

Graph Search II

A release-checked medium problem for training Expected Value.

Question

We have an undirected graph with $11$ nodes. For every node, you are able to access any other node (not including itself), all with an equal probability of $1/10$. Given this graph what is the expected number of steps to reach all nodes at least once (rounded to the nearest step)?

Practice focus

This Probability problem is tagged 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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