SAT: Ratios, Rates & Proportions Glossary
10 essential terms — because precise language is the foundation of clear thinking in SAT: Ratios, Rates & Proportions.
Showing 10 of 10 terms
The unchanging value $k$ in a proportional relationship $y = kx$, equal to the unit rate.
A method for solving proportions: if $\frac{a}{b} = \frac{c}{d}$, then $ad = bc$.
A systematic method for converting between units by multiplying by conversion factors expressed as fractions equal to 1.
A relationship in which $y = kx$ for a positive constant $k$; the ratio $\frac{y}{x}$ remains constant.
A relationship in which $xy = k$; as one variable increases, the other decreases proportionally.
An equation stating that two ratios are equal, such as $\frac{a}{b} = \frac{c}{d}$.
A ratio that compares two quantities measured in different units, such as miles per hour or cost per item.
A comparison of two quantities by division, written as $a:b$ or $\frac{a}{b}$.
The constant ratio between corresponding lengths in similar figures or between a model and the real object.
A rate expressed per one unit of the denominator quantity, making comparison and scaling straightforward.