0
Wiki User
6.9
It is: 71
61 67 71
67 or 71
71.
They are: 53, 59, 61, 67, 71 and 73
Halfway between them is 69.
2OO
67 71 73
59, 61, 67, 71 and 73.
53, 59, 61, 67, 71, 73.
71