Here's the math:
[tex] \frac{(26 + \frac{1}{3} ) - (10 + \frac{1}{4} )}{2} [/tex]
[tex] \frac{(79/3 - 41/4)}{2} [/tex] =
[tex] \frac{(79*4 - 3*41)}{(12*2)} [/tex] =
[tex] \frac{(316 - 123)}{24} [/tex] =
[tex] \frac{193}{24} [/tex] =
8 [tex] \frac{1}{24} [/tex] inches from the edge