When n/a is the cash fate and n/a is the 31-day pass how many types of fare are there?
create table table_20803241_1 (type_of_fare varchar, cash_fare varchar, day_pass varchar, PRIMARY KEY (type_of_fare))
select count(type_of_fare) from table_20803241_1 where 31 - day_pass = "n/a" and cash_fare = "n/a"