(1) by divisiblity rule any number subtracted with its reflection will be divisible by 9
because if you write say a 5 digit number it could be as below
number = 10000a+1000b+100c+10d+1e
reflection is =10000e+1000d+100c+10b+a
number -reflection=9999a+990b-0c-990d-9999e
so we know that any number (be any number of digit) subtracted by reflection will be divisible by 9
(2) A and B are not equal
(3)if 3
then
(3+x)/3 is always greater than (5+x)/5
as (3+x)/3 -(5+x)/5 = x/3-x/5=2x/15 if x>0 2x/15> 0
since x lies between 3 and 5 2x/15 is always positive
hence A>B