Constant of proportionality from a table

I can write an equation of the form  to represent a proportional relationship described by a table or a story.

This is the standard equation form for a proportional relationshiop

Multiple Choice

What does the k stand for in the equation?

• constant of proportionality

• unit rate

• independent variable

• dependent variable

A recipe says that 2 cups of dry rice will serve 6 people.

How many people will 1 cup of rice serve?

A recipe says that 2 cups of dry rice will serve 6 people. How many people will 12 cups of dry rice feed?

12 cups of dry rice will feed 36 people.

A recipe says that 2 cups of dry rice will serve 6 people.

So the constant of proportionality is 3 and the equation is y = 3x

Multiple Choice

A new recipe says that 6 spring rolls will feed 3 people. Which equation can be used to represent the relationship between people (y) and spring rolls (x)?

• y = 2x

• y = 1/2x

• y = 3x

• y = 1/3x

To create an equation from the table

divide the y's by the x's to find the constant of proportionality. y = 3x

Fill in the Blank

Write the equation that could represent the table.

Today you will complete constant of proportionality from tables with equations) and writing proportional equations from tables