CREATE TABLE table1
([account_number] int, [Amount] int)
;
INSERT INTO table1
([account_number], [Amount])
VALUES
(13, 40),
(14, 30),
(14, 30),
(13, 60),
(14, 10)
;
SELECT Sum(amount) as amou FROM (SELECT Sum(amount) as amount FROM table1 WHERE account_number IN (13, 14) GROUP BY account_number)