Forumla Conversion

Hello,

I have a subtable which has some fields that does some calculations (see screenshot).

The profit field is worked out on Project Cost Quoted - Project Time Cost, and Project Time Cost is worked out on sum of a time field / 3600000 * 85 (our hourly rate)

 When I then try and add the profit field to the main view, its showing as a time and not the number field and I cannot seem to convert

 Any help would be greatly appreciated