Question

If you weigh 100 kg, how much would you weigh if all the water were removed from your body?

Answer 1

Well 60% of your body is water. That means that the 40% is not water. If you weigh 100kg then you would weigh 40kg without water.

Answer 2

Generally, 60% of the mass of body is water.

So, amount of water in 100 kg person is:

$100 kg\times \frac{60}{100} = 60 kg$

In order to calculate the mass of a person if all the water were removed, then:

$Mass of the body - Mass of the content of water in the body$

Mass of the body = $100 kg$[

Mass of the content of water in the body = $60 kg$

Substituting the values:

Mass of a person if all the water were removed = $100 kg -60 kg = 40 kg$.

Hence the mass of a person who weighs $100 kg$ will weigh $40 kg$ if all the water were removed from the body.