It is important that the units of measurement for the masses will be expressed in one unit only. For the purpose of illustration in this problem, we express the masses in kilograms. Hence, the mass of Springer Spaniel is equal to 20.49 kg. With this concept, we determine the mass of Cocker Spaniel.
Mass of Cocker Spaniel = 20.49 kg - 7.59 kg = 12.9 kg
From this calculated mass, we determine the mass of the Newfoundland,
Mass of Newfoundland = 12.9 kg + 52.656 kg = 65.556 kg
The difference of the weights of Newfoundland and Springer Spaniel,
D = 65.556 kg - 20.49 kg = 45.066 kg
ANSWER: 45.066 kg
