A floating object displaces its own weight. All you have to do is convert 100 tons to an SI unit of weight (force).
1 ton = 2,000 pounds 100 tons = 200,000 pounds
The SI unit of force (weight) is the Newton. On Earth, 1 kg of mass weighs 9.8 newtons, or 2.205 pounds.
(200,000 pounds) x (9.8 newtons / 2.205 pounds) = 888,900 newtons (rounded)
A 100-ton floating ship displaces a weight of water equal to its own weight, which is 981,000 N. This corresponds to a volume of approximately 100 m³ of water displaced. This conclusion is based on Archimedes' principle of buoyancy.
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