CREATE TABLE table_18332845_2 (departure VARCHAR, going_to VARCHAR, arrival VARCHAR)

What is the departure for Peterborough East whose arrival time is 12.40?
SELECT departure FROM table_18332845_2 WHERE going_to = "Peterborough East" AND arrival = "12.40"
SELECT "departure" FROM "table_18332845_2" WHERE "12.40" = "arrival" AND "Peterborough East" = "going_to"