Log time expense in minutes

For the hours entry - is there any way to change the data entry format to minutes rather than a percentage so I can just input the actual time spent? For example if I work on something for 2:30 I must enter the time total as 2.5. If I work on a project for 2:41 is it kinda difficult to figure out what that equals in percentage or a decimal equivalent. It would probably be like 2.6532 or something.