Harry's spell casting class lasts for

2
5
6
2
6
5

2, start fraction, 5, divided by, 6, end fraction hours each day. Today, he has been in the class for
1
2
5
1
5
2

1, start fraction, 2, divided by, 5, end fraction of an hour so far.
How much more time is left in the class?

Harry has been in the class for a total of:

2 + 5 + 6 + 2 + 6 + 5 = 26 hours

He has completed:

1 + 2/5 = 7/5 hours

Therefore, there is still time left in the class:

26 - 7/5 = 133/5 - 7/5 = 126/5

So there is still a total of 126/5 hours or 25 1/5 hours left in the class.