如何在Excel中将小数时间转换为hh：mm时间格式

I have looked at all the options I can find on this forum, but I am unable to solve my problem. this may very well be because I only have basic excel skills. simple question..how do I convert a decimal time ie 9.25 into hh:mm format ie 09:25 ? I need to do this as I am using existing data that requires rounding to 15 mins + 2mins and I can only do this in hh:mm format. Many thanksI have looked at all the options I can find on