Question 74091
this problem is a triangle withe the hypotenuse (1/2 diameter=16) and one side =11. thus we have a right triangle 
a^2+11^2=16^2
a^2=256-121
a^2=135
a=11.62 for the third side which is 1/2 of the length of the cord. 
thus the length of the cord is 2*11.62=23.24 yards.