Payroll time sheet calculation where time exceeds 24 hours

Hello,

I am trying to format a payroll time sheet to calculate gross pay using time that can, but not necessarily will, exceed 24 hours, multiplied by an hourly rate. I'm aware of using [hh]:mm, however, even with that formula, a value of twenty seven hours (27:00), for example, is still displayed as (1/1/1900 1:00:00 AM), even though the cell shows 27:00. Not sure what I am missing. To keep this problem simple, let's assume that there are two cells of twenty seven hours (27:00) that need to be added together and multiplied by a rate of pay.

Thank you for your time and attention to this matter.