The number of kilograms of water in the human body varies dirctly as the mass of the body. An 84-kg person contains 64-kg of water. How many kg of water is in a 63-kg person?
water = k(mass) , where k is a constant
given water = 64 kg when mass = 84 kg
64 = k(84)
k = 64/84 = 16/21
water = (16/21)(mass)
when mass = 63
water = (16/21)(63) = 48 kg
80.try doing it. It easy
The number of kilograms W of water in a human varies directly to the mass of the body. A 96_kg person contains 64 kg of water. How many kilograms of water are in a 60_kg person?
To solve this problem, we need to first determine the constant of variation between the mass of the body and the number of kilograms of water.
We are given that an 84-kg person contains 64-kg of water. This gives us one data point, which we can use to find the constant of variation.
Let's call the mass of the body "m" and the number of kilograms of water "w." We can set up the proportion:
m / w = 84 / 64
Now, we can use this proportion to find the constant of variation:
m / w = 84 / 64
Cross-multiplying, we get:
64m = 84w
Dividing both sides by 84w, we get:
m / w = 64 / 84
Simplifying the right side, we have:
m / w = 8 / 11
Now that we have the constant of variation, we can use it to find the number of kilograms of water in a 63-kg person.
Let's call the unknown number of kilograms of water in the 63-kg person "x." We can set up the proportion:
63 / x = 8 / 11
Cross-multiplying, we get:
11 * 63 = 8 * x
Simplifying, we have:
693 = 8x
Dividing both sides by 8, we get:
x = 86.625
Therefore, a 63-kg person would contain approximately 86.625 kg of water.