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Expected lengths of stick pieces

A stick of length 11 is broken at two points chosen independently and uniformly at random, producing three pieces.

What are the expected lengths of the shortest, middle, and longest pieces?

Show a hint

For any tt, compute P(shortest>t)P(\text{shortest} > t) and P(longest>t)P(\text{longest} > t), the survival-function route E[X]=0P(X>t)dtE[X] = \int_0^\infty P(X > t)\,dt avoids messy densities. For the longest, use inclusion-exclusion over the three pieces.

Your answer

This one is open-ended. Work it through, then check your reasoning against the full solution.

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