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Corrected the error in the number of breaks $n-1$ and the resulting number of sides $n$. Tightened the prose. Clarified the title to refer to area.

Expected area of a pentagon formed from a randomly broken stick

Suppose we break a stick of length one at four randomly and independently chosen points and that the resulting pieces form a pentagon.

Such a pentagon can be formed with probability $1-(5/16) = {11\over16}$ (see https://atlas.mat.ub.edu/personals/dandrea/emiliano_gomez.ps, which states that an $n$-gon is formed from $n-1$ breaks with probability $1-{n\over2^{n-1}}$).

Using this distribution of lengths and assuming that a cyclic pentagon has been formed, what is the expected value of the pentagon's area?