If the bar is in the center of the door then we know that there is the same amount of space on each side of the bar. Call this space 's'. This is what we need to find. We also know the total width of the door and the total length of the bar. With this info we can set up and equation to represent the relationship:
[tex]s=\frac{26\frac{1}{3} - 10\frac{1}{4}}{2}[/tex]
and then solve for s. This is easer to do if we convert the two fractions to a common base and rearrange the equation so that instead of dividing by 2, we instead multiply by 1/2:
[tex]s=26\frac{4}{12} - 10\frac{3}{12} \times \frac{1}{2} = 13\frac{1}{12} \times \frac{1}{2} = \frac{193}{12} \times \frac{1}{2} = \frac{193}{24} = 8 \frac{1}{24}inch[/tex]