Summary:
When running a report like the User Hour Details report, the time that is displayed against the user is in the form of Decimals. This sometimes needs to be converted to a format that can display the time in Hours and Minutes rather than the decimal value. This conversion would require a custom columns to be made and thus needs the appropriate formula to get this working.

Resolution:
When using the reports like the User Hour Details report, use the formula to convert the time displayed in decimals to the hh:mm format. A custom column can be created by clicking on the Settings button on the report and under the General tab. at the bottom of the page, click on Add to add a new custom column. The New custom column can have a customized name and the main box should have the below code snippet:

left(NumberToText(RegularHours), Find(NumberToText(RegularHours),"."))+" : "+ left(numbertotext(roundhalfeven(texttonumber(mid(NumberToText(RegularHours), Find(NumberToText(RegularHours),"."),len(NumberToText(RegularHours))-
Find(NumberToText(RegularHours),".")))*60)),
find(numbertotext(roundhalfeven(texttonumber(mid(NumberToText(RegularHours),
Find(NumberToText(RegularHours),"."),
len(NumberToText(RegularHours))-Find(NumberToText(RegularHours),".")))*60)),"."))

Here, the custom column converts the time displayed in the field RegularHours. If there is any other field that display the time in decimals and needs to be converted, that field name has to be input in place of RegularHours.