SQL Server Management Studio is automatically rounding my calculation

You can
Select cast(field as decimal(18,2)) from table

If you give us your query and sample data we can give more specific help.

SELECT (A.ActualEnd - A.ActualStart - Isnull(A.Lunch, 0)) / 60 AS 'FinalDuration'

with real values, the result will be 7 instead of 7,25
SELECT (780 - 300 - 45) / 60

FYI, values are minutes from midnight
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Using CAST like suggested is still giving me the wrong results, I now optain 7.00 instead of 7.25

(780 - 300 - 45) / 60.0
Is resulting 7.25000

:)

Thank You