7 h. 30 min.
3 hours 30 minutes = 3.5 hours
2.5 hours
III hours, XXX minutes
450 minutes.
5.5 hours. (30 minutes is half an hour, expressed as 0.5hrs, or every 0.1hrs is 6.0min.)
You can write 6 and a half hours as 6.5 hours or 6 hours and 30 minutes. In some contexts, it can also be expressed as 6:30 when using a time format.
You can write "4 hours and a half" as "4.5 hours" or "4 hours and 30 minutes." Both formats clearly convey the same duration.
You can write 2.5 hours. This is the same as 25/10 hours. 1/10 of an hour is 6 minutes so 5/10 is 30 minutes. 2.5 hours is the same as writing 2hours 30 minutes. 3.75 hours = 3 hours 45 minutes 1.25 hours = 1 hour 15 minutes etc etc
4
To write seven and a half hours, you can express it as 7.5 hours or as 7 hours and 30 minutes. This is a decimal representation of time where the whole number represents the hours and the decimal represents the fraction of an hour in terms of minutes. It is a common way to express time in a more precise and standardized format.
2 hours 30 minutes
1/2 hour 30 minutes 0.5 hours