Solution:
Let's call the length of the crease "c," and the dimensions of the paper are 10 cm and 24 cm.

Using the Pythagorean Theorem:
c^2 = 10^2 + 24^2
c^2 = 100 + 576
c^2 = 676
c = sqrt{676}
c = 26

So, the length of the crease is 26 cm.