Time scheduling problem

I am trying to create a schedule with day parts, ideally as I insert start times in one column and minutes in another I'd like to create a formula to add up the minutes. However when I create the time formula I get this in the 'show formula
0,0625
0,14375
0,145833333333333
0,152083333333333
0,152777777777778
4.40:00
0,200694444444444
0,241666666666667
0,243055555555556
0,249305555555556
0,25
0,256944444444444
0,263888888888889
0,270833333333333
Can anyone help. Or does anyone know of such a template