# Permutations\Combinations from digits

Using digits 1,2,3,4,5,7 only, how many numbers could be made that are between 2500 and 5000, if a digit is not repeated?

(If it had been 2000-5000, that would have been easy!!!)

The answer at my level should only use $^nP_{r}$, $^nC_{r}$ and\or factorial notation.

-