How do I calculate maximum calories burned in a 60-minute workout a few times a week?

How do I calculate maximum calories burned in a 60-minute workout a few times a week? If running burns 9 calories per minute, aerobics burns 6 calories per minute, and rowing burns 7 calories per minute. I want to perform all three exercises to work different muscle groups. My constraints are run for at least 5 minutes, row for at least 15 minutes and aerobics should be no more than 30 minutes. How many minutes should be performed for each exercise to burn the maximum calories?