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In how many ways can three letters (not necessarily distinct from one another) be selected from the letters of the word PARALLELOGRAMS?

There are 50 distinct lines $L_1, L_2, ..., L_{50}$. All lines $L_{4n}$, where n a positive integer, are parallel to each other. All lines $L_{4n-3}$, where n is a positive integer, pass through a point P. The maximum possible number of points of intersection of pairs of lines in the set $\{L_1, L_2, ...\}$ is