Well, one example would be how much space is in a cardboard box, to ship something to a friend or relative. We know the three measurements: L = Length, W = Width, and H = Height.
And the formula for a volume of a cube is: V = L*W*H
So say that: L = 6 , W = 10 Feet, and H = 3 Feet. By using the formula above we get the equation: V = 6*10*3 And that equals: 180 Feet. So the volume of the box, or the space you have to send something is 180 square feet.
Does this help?
The link I used for some of this info, which has other useful math models is: https://www.mathsisfun.com/algebra/mathematical-models.html