Half of the difference of a number and 11

Question

Half of the difference of a number and 11

Answer 1

(x-11)/2

but

usually the "difference" is positive

so

lx-11l/2 is the absolute value of half x-11 which is

(x-11)/2 if x>11

and

(11-x)/2 if x<11

they're both zero if x=11

two vertical lines in front and back are the absolute value signs.

If you did allow the "difference" to be negative

then

(x-11)/2 would be correct, not (11-x)/2