Directly and Inversely Proportional

Directly Proportional

Directly proportional: when one amount increases, another amount increases at the same rate.

The symbol for “directly proportional” is ∝

Inversely Proportional

Inversely Proportional: when one value increases, at the same rate that the other decreases.


 Directly ProportionalInversely Proportional
Have more workersYou pay moreWork time is shorter

How many spending ∝ workers

Constant of Proportionality

Constant of proportionality is the value that relates two amounts.

 can be written asnote
spending = 10 x workersy = kxwhere k is Constant of Proportionality
Work time = 10 / workersy = k/xwhere k is Constant of Proportionality

Learn More

Zero Product Property

Partial Sum

General Form of Equation of a Line

Finding an Angle in a Right Angled Triangle

Algebra Index