VOR question
Q. assuming the maximum likely error in vor to be 5.5*,what is maximum distance apart that beacons can be situated on the centre line of a UK airways in order that an aircraft can guarantee remaining within the airways boundary?
a. 54.5 nm
b. 109nm
c. 66nm
d. 132nm
plz someone explain why the answer is 109 nm ........what the logic behind this question
thanks for help