Flashcard 3 - Next Generation Quantitative Reasoning, Algebra, and Statistics Flashcard Set for the ACCUPLACER Test

When quantities relate through a constant value, a proportion can be created to solve for an unknown quantity.

For example, a 40 ft tree casts a 12 ft shadow. How long is the shadow cast by a 12 ft pole?
The ratio between the height of an object and its shadow is equivalent across objects, so:

\(\frac{40}{12} = \frac{12}{x}\), which gives \(x = \frac{144}{40}\)