Time Format from Decimal Number to Hours and Minutes (hh:mm)

I have been using Zoho Analytics for some time now, and I have a query table that combines data from three datasheets (Calls, Desk and Projects data coming from different Zoho moduels). One of the columns contains Hours, as a decimal number, eg. 0.75 would refer to 45 minutes. I'd like to convert this to the more common hh:mm format, so 0.75 would be 0:45, or 2.50 would be 2:30. I would like this time to behave as a number so it can be used in sums.

I've tried to do this using numerous methods, but have been unsuccessful thus far. I've tried using the time_format function in Zoho Analytics, but this used strings as it's parameters. I need the output to behave like numbers so they can be added together etc. I've tried changing the format of the columns in their original datasheets, before the query table. However, Zoho doesn't allow me to create the columns that are required here.

So essentially, I need to convert time as a decimal number to the hh:mm format to be used and displayed in a query table and multiple tables/graphs to be placed on a dashboard. Any help on this matter would be really appreciated.