Explanation:

lets assume x,y,z are three digit and y is middle digit in number .

lets assume x>z

100x+10y+Z-(100z+10y+x)=594

99x-99z =594

99(x-z) =594

x-z = 594/99=6

x= z+6

as Z is starting digits in 3 digit number so z must be greater than Zero, so minimum value 0f z must be 1

so x = Z+6 =7, those 3 digit number will be 107 & 701.