Need to convert 21:45 to 21.75
DECLARE @x TABLE(col DATETIME);

INSERT @x SELECT '20150901 21:45';

SELECT col, 
  d = CONVERT(CHAR(10), col, 101), -- AMBIGUOUS, REGIONAL, NOT RECOMMENDED!
  t = CONVERT(DECIMAL(4,2), DATEDIFF(MINUTE, CONVERT(DATE,col), col)/60.0) 
FROM @x;


Results:

col                        d             t
-----------------------    ----------    -----
2015-09-01 21:45:00.000    09/01/2015    21.75