A rancher’s herd of 250 sheep grazes over a 40-acre pasture. He would like to find out how many sheep are grazing on each acre of the pasture at any given time, so he has some images of the pasture taken by the state department of agriculture’s aerial photography division. Here are three samples of the images.

Sample 1 4
Sample 2 1
Sample 3 9

If the sheep were equally "spread out" across all of the 40 acres, how many sheep would you expect to find on average on each acre?