# NMO Problem 1

Algebra Level 5

A five-digit positive integer $$abcde_{10}$$ ($$a\neq 0$$) is said to be a range if its digits satisfy the inequalities $$a<b>c<d>e$$. For example, $$37452$$ is a range. How many ranges are there? This problem is from the NMO.This problem is part of this set.

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