Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_87 (silver INTEGER, total VARCHAR, bronze VARCHAR, nation VARCHAR)

### Question ###
What is the average amount of silver medals Montenegro, who has less than 15 bronze and more than 11 total medals, has?

### Accurate SQL ###

SELECT AVG(silver) FROM table_name_87 WHERE bronze < 15 AND nation = "montenegro" AND total > 11