SQL Server 2017

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CREATE TABLE T(
  StartHour INT,
  StartMinute INT,
  StartSecond INT,
  EndHour INT,
  EndMinute INT,
  EndSecond INT,
  [Date] DATE
);

INSERT INTO T VALUES
(10,  15,  0 ,  10,   30,   30, '2018-11-27'),   
(10,  15,  0 ,  10,   30,   30, '2018-11-30'),   
(6 ,  10,  30,  6 ,   23,   45, '2018-12-02'),   
(8 ,  10,  0 ,  8 ,   53,   45, '2018-12-02'),   
(10,  5 ,  13,  10,   55,   23, '2018-12-02');
5 rows affected

SELECT [Date],
       CAST(DATEDIFF(Second, StartTime, EndTime) / 60 AS VARCHAR) + ':' +
       CAST(DATEDIFF(Second, StartTime, EndTime) % 60 AS VARCHAR) [MM:SS]
FROM
(
  SELECT [Date],
         TIMEFROMPARTS(StartHour, StartMinute, StartSecond, 0, 0) StartTime,
         TIMEFROMPARTS(EndHour, EndMinute, EndSecond, 0, 0) EndTime
  FROM T
) TT;


Date
MM:SS


27/11/2018 00:00:00
15:30

30/11/2018 00:00:00
15:30

02/12/2018 00:00:00
13:15

02/12/2018 00:00:00
43:45

02/12/2018 00:00:00
50:10


SELECT [Date],
       CAST(SUM(DATEDIFF(Second, StartTime, EndTime)) / 60 AS VARCHAR) + ':' +
       CAST(SUM(DATEDIFF(Second, StartTime, EndTime)) % 60 AS VARCHAR) [MM:SS]
FROM
(
  SELECT [Date],
         TIMEFROMPARTS(StartHour, StartMinute, StartSecond, 0, 0) StartTime,
         TIMEFROMPARTS(EndHour, EndMinute, EndSecond, 0, 0) EndTime
  FROM T
) TT
GROUP BY [Date];


Date
MM:SS


27/11/2018 00:00:00
15:30

30/11/2018 00:00:00
15:30

02/12/2018 00:00:00
107:10

Date	MM:SS
27/11/2018 00:00:00	15:30
30/11/2018 00:00:00	15:30
02/12/2018 00:00:00	13:15
02/12/2018 00:00:00	43:45
02/12/2018 00:00:00	50:10