posted by emmy .
you have five bales of hay. for some reason,instead of being weighed individually, they were weighed in all possible combinations of two:bales 1 and 2, bales 1 and 3,bales 1 and 4, bales 1 and 5, bales 2 and 3, bales 2 and 4, and so on. The weights of each of these combinations were written down and arranged in numerical order, without keeping track of which weight matched which pair of bales. The weights in kilograms were 80, 82, 83, 84, 85, 86, 87, 88, 90, and 91. Find out how much each bale weighs. In particular, you should determine if there is more than one possible set of weights, and explain how you know. Try to find an easier and more efficient way to find the weights.