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_55 (frequency_mhz INTEGER, erp_w INTEGER)
### Question:
What is the frequency MHz of the ERP W's greater than 250?
### Answer:
SELECT AVG(frequency_mhz) FROM table_name_55 WHERE erp_w > 250