# Increasing - decreasing

Probability Level 3

A 5-digit number $\overline{abcde}$ is called decreasing if $a > b > c > d > e$. A 5-digit number $\overline{abcde}$ is called increasing if $a < b < c < d < e$. What is the (absolute) difference in the number of increasing and decreasing 5-digit numbers?

Details and assumptions

The number $12=012$ is a 2-digit number, not a 3-digit number.

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