Q:

Derive the combination and escape the room!

You awake to find yourself on the floor of what appears to be a cold cell. You don't know how you got there but you're sure no one is coming for you and you need to get out. The stone room has no windows and the only exit is a large oak door.
On the door is some engraved writing and three dials like those of a combination lock (numbered 1 through 50). The door is locked of course. It's got a deadbolt and its hinges are on the other side.
The writing reads:
DERIVE THE COMBINATION:

I. THX XXMBER OF XEXTEXX XX THE XXXXXBXT (LXTXX, NOT GXEEK).

II. TXE NXMXXX OF WXXXX TXXXS IN XX XCTXVE

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

NOW 
CAN YOU 
RESOLVE IT?

It seems parts of the writing have been scratched out. The line below II. is completely scratched out and there is nothing to be read.
How do you get out of here?
Hint:

 The third line seems completely unreadable. However, the peculiar arrangement of the final three lines stands out to you. Why were the lines broken like that? It seems like it might mean something...

A:

I think the combination is:

 23 02 30 (or possibly 10 09 47 see below)

First Line:

 26 -> THE NUMBER OF LETTERS IN THE ALPHABET. (LATIN, NOT GREEK).

Second Line:

 6 -> THE NUMBER OF WHOLE TONES IN AN OCTAVE.

Lastly:

 The last three lines start N, C, R and 26 nCr 6 is 230230, which splits nicely into 3 numbers between 1 and 50: 23, 02, 30

Possible Alternative

 If 23 is used instead of 26 for the number of letters in the latin alphabet, as suggested in the answer comments, then 23 nCr 6 is 100947, which still works as a combination: 10, 09, 47

A:

Partial Progress:

 I: THE NUMBER OF LETTERS IN THE ALPHABET. (LATIN, NOT GREEK). This is 26.
 II: THE NUMBER OF WHOLE TONES IN AN OCTAVE. This is 6.

I still can't understand how III is possible...

A:

The first two lines read:

THE NUMBER OF LETTERS IN THE ALPHABET (LATIN, NOT GREEK) and THE NUMBER OF WHOLE TONES IN AN OCTAVE

giving you the numbers

 26 and 6

New possible answer to the third line:

Perhaps "derive the combination" is referring to taking the derivative of something, in which case it would be relevant that all the numbers are scratched out with X's. The third line is 62, which is too long, but if you combine the X's from the first two, there are 33 X's (33X), and if you then derive this combination, you get 33.

