Table schema:
CREATE TABLE dorm (dorm_name VARCHAR, dormid VARCHAR); CREATE TABLE student (age INTEGER, stuid VARCHAR); CREATE TABLE lives_in (stuid VARCHAR, dormid VARCHAR)

Question: Find the average age of students living in each dorm and the name of dorm.
SQL: SELECT AVG(T1.age), T3.dorm_name FROM student AS T1 JOIN lives_in AS T2 ON T1.stuid = T2.stuid JOIN dorm AS T3 ON T3.dormid = T2.dormid GROUP BY T3.dorm_name