The smallest number is equal to the original number. What is the original number?

A three-digit number, rearrange its digits into a new three-digit number, and the largest number MINUS the smallest number is exactly equal to the original number. What is the original number?

Suppose that the three digits that make up the original three digits are a, b, c and a >； respectively; b & gtc，

The largest three digits are abc= 100a+ 10b+c,

The smallest three digits are cba= 100c+ 10b+a,

So abc-cba

=( 100 a+ 10 b+c)-( 100 c+ 10 b+a)

=99 (AC)

Because 2≤a-c≤9

So the possible values of the first three digits are:

198,297,396,495,594,693,792,89 1,

Because 981-189 = 792 ≠198,

So the original three digits are not equal to 198,

After verification, the original three digits are not equal to 297,396,594,693,792,891,

So the first three digits are 495,

954-459=495.

A: The original number was 495.