Proportional Function Math Example 1

Follow the full solution, then compare it with the other examples linked below.

easy

The weight of water is proportional to its volume.

5

liters weighs

5

kg. Write the function, find the constant of proportionality

k

, and compute the weight of

8.5

liters.

Answer

W(V) = V

;

k = 1

kg/L;

W(8.5) = 8.5

Direct proportionality

y=kx

means the ratio

y/x

is constant. Here the density of water is

1

kg/L, making it a clean example where

k=1

About Proportional Function

A proportional function has the form $f(x) = kx$ for a constant $k \neq 0$ — it passes through the origin and the ratio $f(x)/x = k$ is constant.

Determine whether [formula] is proportional to [formula] given the table: [formula] and [formula]. I

Hooke's Law states spring force is proportional to stretch: [formula]. If [formula] N when [formula]

Explain why [formula] is NOT a proportional function, and find the value of [formula] that would mak