Ratios, Proportions, and Proportionality

Front

What is a proportional relationship?

Back

A proportional relationship is a relationship between two quantities where the ratio of one quantity to the other is constant.

Front

What does it mean for a graph to be proportional?

Back

A graph is proportional if it is linear and passes through the origin (0,0).

Front

How can you identify a proportional relationship from an equation?

Back

An equation represents a proportional relationship if it can be written in the form y = kx, where k is a constant.

Front

What is a ratio?

Back

A ratio is a comparison of two quantities, showing how many times one value contains or is contained within the other.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the two ratios and set the products equal to each other.

Front

What is the unit rate?

Back

The unit rate is a ratio that compares a quantity to one unit of another quantity.

Front

If 4 apples cost $2, what is the cost of 1 apple?

Back

$0.50

Front

What is the constant of proportionality?

Back

The constant of proportionality is the constant value (k) in the equation y = kx that represents the ratio between y and x.

Front

How do you determine if two ratios form a proportion?

Back

Two ratios form a proportion if their cross products are equal.