CREATE TABLE table_204_880 (id NUMBER, "year" NUMBER, "competition" CLOB, "venue" CLOB, "position" CLOB, "event" CLOB, "notes" CLOB)

51st position and 31st position were both obtained by this runner at which competition ?
SELECT "competition" FROM table_204_880 WHERE "position" = 51
SELECT "competition" FROM "table_204_880" WHERE "position" = 51