may i have you help to have which formua can calcultion by number to time format! for example
1110 - 916 = "hh:mm"
If you mean 1110 is the time 11:10 and 916 is the time 9:16, you cannot subtract the numbers 1110 - 916, then format as time.
Instead, you must format the numbers as time, then subtract as follows, if A1 is 1110 and B1 is 916:
=TEXT(A1,"00\:00") - TEXT(B1,"00\:00")
formatted as Custom hh:mm.
I assume that B1 is the start time and A1 is the end time. More generally:
=TEXT(A1,"00\:00") - TEXT(B1,"00\:00") + (A1<b1)
That allows for an end time less than the start time because the time period spans midnight; that is, midnight is between the start and end times.