Proportional Relationships

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 quantity is constant.

Front

What is the unit rate?

Back

The unit rate is the ratio of two measurements in which the second term is 1. For example, if a car travels 60 miles in 1 hour, the unit rate is 60 miles per hour.

Front

How do you identify a proportional relationship from a graph?

Back

A proportional relationship can be identified from a graph if the line passes through the origin (0,0) and is straight.

Front

What does the equation y = kx represent?

Back

The equation y = kx represents a proportional relationship where k is the constant of proportionality.

Front

If a recipe calls for 2 cups of flour for 4 servings, how much flour is needed for 10 servings?

Back

5 cups of flour (2 cups for 4 servings means 0.5 cups per serving; 0.5 cups x 10 servings = 5 cups).

Front

What is the constant of proportionality in the equation y = 8x?

Back

The constant of proportionality is 8.

Front

If a car travels 120 miles in 2 hours, what is the unit rate?

Back

The unit rate is 60 miles per hour (120 miles ÷ 2 hours = 60 miles/hour).

Front

Which of the following represents a proportional relationship: y = 3x + 2 or y = 4x?

Back

y = 4x represents a proportional relationship because it can be expressed in the form y = kx.

Front

What is the cost per slice if a pizza with 8 slices costs $12?

Back

The cost per slice is $1.50 ($12 ÷ 8 slices = $1.50 per slice).

Front

How can you tell if a table of values represents a proportional relationship?

Back

A table of values represents a proportional relationship if the ratios of corresponding values are constant.