At the beginning of the exercise, three soldiers, named Ike, Jay and Kay, were at three different points equidistant from a target. Ike was 4 kilometers from Jay, and also 4 kilometers from Kay.

Then Jay started moving inward, directly toward the target. He stopped short of the target, at a point different from his original location, but again 4 kilometers from Ike.

At this point the distances between any two of Ike, Jay, Kay and the target were all whole numbers of kilometers.

In his new position, how far is Jay from Kay?