I have a (time) table with numbers such as:

1.28 , 0.15, etc...where the first digit represents the amount of minutes
and the two decimals represent seconds.

in the example: 1.28 = 1 minute and 28 seconds and I would like to convert
in excel
these tabulated times into a 00:00:00 format. So the outcome I'm looking for
in the conversion cell would be (for 1.28) 00:01:28 ; for 0.15 = 00:00:15 and
so on

could anyone help me?? and if you'd be so kind, could you explain the
formula to me so I can get the logic? thanks!!