Let \(a_1, a_2, \cdots ,a_8\) be the weights of the 8 dogs from the lightest to heaviest (in pounds).
For the maximum range, we assume that \(a_1 = a_2 = \cdots = a_7 = 40\). Then \(5\times 40 + a_8 = 6(55)\), \(a_8 = 130\).
Maximum range = 90 pounds.
