Question

The number of kilograms of water in a human body varies directly as the mass of the body. An 87​-kg person contains 58 kg of water. How many kilograms of water are in a 75​-kg ​person?
nothing kg of water are in a 75​-kg person.

Answer 1

Answer:

50 kg water.

Step-by-step explanation:

We have been given that the number of kilograms of water in a human body varies directly as the mass of the body.

We know that two directly proportional quantities are in form $y=kx$, where y varies directly with x and k is constant of variation.

We are told that an 87​-kg person contains 58 kg of water. We can represent this information in an equation as:

$58=k\cdot 87$

Let us find the constant of variation as:

$\frac{58}{87}=\frac{k\cdot 87}{87}$

$\frac{29*2}{29*3}=k$

$\frac{2}{3}=k$

The equation $y=\frac{2}{3}x$ represents the relation between water (y) in a human body with respect to mass of the body (x).

To find the amount of water in a 75-kg person, we will substitute $x=75$ in our given equation and solve for y.

$y=\frac{2}{3}(75)$

$y=2(25)$

$y=50$

Therefore, there are 50 kg of water in a 75​-kg person.