text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE table_name_98 (platform INTEGER, frequency__per_hour_ VARCHAR, destination VARCHAR)
  ### Question:
  what is the platform when the frequency (per hour) is 4 and the destination is west croydon?
  ### Answer:
  SELECT SUM(platform) FROM table_name_98 WHERE frequency__per_hour_ = 4 AND destination = "west croydon"