If you are usin fx-991 Scientific calculator then it's really easy to convert units into time. You can see a box above the ENG button with a circle and 3 commas ?
for example you want to divide 365 by 565 and want the answer in minutes and seconds then u do this
365 / 565 , press (= )(it will give you the answeer as 0.646) and then press SHIFT and press dot comma box. 0 is the hour 38 are the minutes and 45 are the seconds.