You can put this solution on YOUR website! Consider a right angled triangle.
The vertical side = 60ins (Distance
of chord from centre)
The base side = 25ins (half of the chord)
The radius will now constitute the hypotenuse.
Vertical side^2 + Base side^2 = Hypotenuse^2
60^2 + 25^2 = Hypotenuse^2
Hypotenuse^2 = 4225
Hypotenuse =
Hypotenuse = 65ins
This is the length of the radius.
Hope this helps.
:-)