get rid of the square brackets around the varchar(255) and it will work fine.

For that matter, why are you putting them around the datatypes anyway? I've never seen anyone do that.

select * from persons where (prefix like '%'+@input+'%'
or
firstname like '%'+@input+'%'
or
lastname like '%'+@input+'%')
and address like '%'+@addressinput+'%'

or simply "select 50. / 100"