Getting different results

Hi,

Im trying to calculate how many hrs a user wroked weekly, however i'm getting different results

1) i'm trying to get the time using the 'between' function for a specfic week

Code:

SELECT [userID] , CAST(SUM(workingtime) / 60 AS varchar(5)) + ':' + RIGHT('0' + CAST(SUM(workingtime) % 60 AS varchar(2)), 2) FROM yyyyy where datee between '01/04/2014' and '01/11/2014' group by userID

for user A i'm getting = 58 for that specific week

2)i tried to do the same thing but with a different code, and i get a different result for user A which is 52hrs for that specific week

Code:

SELECT userID, CONVERT(varchar(50), (DATEADD(dd, @@DATEFIRST - DATEPART(dw, datee), datee)), 101), CAST(SUM(workingtime) / 60 AS varchar(5)) + ':' + RIGHT('0' + CAST(SUM(workingtime) % 60 AS varchar(2)), 2) AS Expr1 FROM yyy GROUP BY userID, CONVERT(varchar(50), (DATEADD(dd, @@DATEFIRST - DATEPART(dw, datee), datee)), 101)

I tried to alternate the first and last day of the week but still i don't get the same result?
I'm not sure why i'm getting different results, any help will be appreciated.

Thanks