Now you can fold the 2 lengths so two of the folded lengths are about 1/3 the length of the remaining 2 lengths. Cut the elastic string so you have 4 lengths, with 2 lengths 1/3 the length of the other 2.
Like I said before, the two long lengths may not be long enough to span the distance necessary to have the stanchions in the gym, or the stakes in the back yard, wide enough. So I would recommend that you bite the bullet, and spend another whoppin $2.00 for another package, even though you will have some left over.
Cut the two lengths in one package into thirds, and give a third to your other 2 pitchers. They can use those for the vertical part of the target. Then all they have to do is buy one package each for the horizontal strings.