It is easier to carry two buckets of water in one hand each, than to carry only one in one hand as

core of gravity & core of equilibrium fall within the feet.When the buckets containing equal amount of water are held in both hands, weight is spaced out more evenly than it would be if one had to carry a single bucket. For balancing the weight, the core of gravity & the core of equilibrium should fall, in the present case, within the feet.