tell me the total number of decile with a roll showing 251.
CREATE TABLE table_name_90 (decile VARCHAR, roll VARCHAR)
SELECT COUNT(decile) FROM table_name_90 WHERE roll = 251
### Context: CREATE TABLE table_name_90 (decile VARCHAR, roll VARCHAR) ### Question: tell me the total number of decile with a roll showing 251. ### Answer: SELECT COUNT(decile) FROM table_name_90 WHERE roll = 251