CREATE TABLE table_29242 ("Train No." FLOAT, "Train Name" CLOB, "Arrival" CLOB, "Departure" CLOB, "Days" CLOB, "Platform No." CLOB)

How many trains depart at 17:30?
SELECT COUNT("Train No.") FROM table_29242 WHERE "Departure" = '17:30'
SELECT COUNT("Train No.") FROM "table_29242" WHERE "Departure" = '17:30'