To find the length of any arc:
Find out what fraction of 360°, or in this case, 2π radians, the angle is.
Multiply that by the circumfrence of the circle. (2πr, of course)
The left side of the walkway can be found with
[tex]\frac{1.57}{2\pi}*2\pi25\ +\ \frac{1.32}{2\pi}*2\pi30 = 78.85[/tex]
The right side of the walkway can be found with
[tex]\frac{1.57}{2\pi}*2\pi30\ +\ \frac{1.32}{2\pi}*2\pi25 = 80.1[/tex]
The difference between 80.1 and 78.85 is 1.25 ft.