CREATE TABLE Student (
    student_id CHAR(7),
    student_name VARCHAR(30),
    address VARCHAR(30));

CREATE TABLE Exam (
    student_id CHAR(7),
    score INT);

INSERT INTO Student VALUES
('0000001','Yamada Ichiro','Tokyo'),
('0000002','Suzuki Akira','Ibaraki'),
('0000003','Yamada Jiro','Chiba'),
('0000004','Sato Hanako','Saitama'),
('0000005','Yamada Saburo','Saitama'),
('0000006','Tanaka Momoko','Saitama');

INSERT INTO Exam VALUES
('0000001',90),
('0000002',82),
('0000003',97),
('0000004',43),
('0000005',31),
('0000006',65);

INSERT INTO Student
VALUES('2503082','Shimoda Hinata','Saitama');

INSERT INTO Exam
VALUES('2503082',60);

SELECT AVG(score) FROM Student JOIN Exam 
ON Student.student_id = Exam.student_id WHERE address='Saitama';

#SELECT * FROM Student;
#SELECT * FROM Exam;