Multiplying hours/minutes in a calculated column

Question

I am trying to use calculated columns to sum the difference between two times then multiply that result by a number.

The SharePoint list looks like this:

The "Start Time" and "End Time" columns are TEXT, the reason for this is because the list is being populated from Microsoft Form, which doesn't have a native time control so users are inputting this as free text.

"Time Diff" is a calculated column with the following calculation

=TEXT([Start Time]-[End Time],"h:mm")

This appears to be working as expected and is showing the time difference between the two time fields.

The next step is I want to multiply the result in "Time Diff" by the number in "Employee Count". Again this is a calculated column with the following formula

=[Time Diff]*[Employee Count]*24

As you can see it is working where the "Employee Count" is 2, but if it is 1 the sum isn't correct, the "Calculated Total Time" and "Time Diff" column should be the same. I am frustratingly close but I can't see to get this sum right, hopefully someone will be able to help?

Thanks in advance Rob

Answer 1

You should be able to achieve the goal with this formula:

=CONCATENATE(INT([Time Diff]*[Employee Count]*24),":",TEXT(MOD([Time Diff]*[Employee Count]*24*60, 60), "00"))

Answer 2

Ok, I can see the issue was between the seat and keyboard here. The "Calculated Total Time" is of course the decimal of the time, so 45 minutes = 0.75 of an hour so that calculation is correct.

Rob