There is 24 hours in a day.
Spending 7 hours sleeping means you have 7 hours less for other things.
24 - 7 = 17
1/4 of the day is basically saying 1/4 of 24 hours, which is 6 hours.
17 - 6 = 11
1/12 of the day is basically saying 1/12 of 24 hours, which is 2 hours.
11 - 2 = 9
You have 9 hours of the day left, in fraction form being:
3/8 of the day left
