SCHEMA:
CREATE TABLE table_name_38 (silver INTEGER, bronze VARCHAR, rank VARCHAR, total VARCHAR)
USER:
On average, what is the number of silver medals for nations ranking higher than 7, with a total of 6 medals and fewer than 2 bronze medals?

QUERY:
SELECT AVG(silver) FROM table_name_38 WHERE rank > 7 AND total = 6 AND bronze < 2