Constant of proportionality

Constant of proportionality

What does this mean? Before we get to that lets take a look at some familiar examples

While exercising yesterday, i had the following information:

12 calories burned in 2 minutes

30 calories in 5 minutes

42 calories in 7 minutes.

Can you figure out how many i would burn in 10 minutes? How can we tell?

The unit rate here is also called the constant of proportionality. A constant is like a ratio in that it is just the numbers from the unit rate.

so here the constant is 6

Multiple Choice

What is the constant of proportionality? 

• 7
• 2
• 8
• 1/2

Multiple Choice

What is the constant of proportionality? 

• 1/3
• 3
• 5
• 10

Multiple Choice

What is the constant of proportionality for this table?

• 1/9

• 9

• 8

Multiple Choice

The constant of proportionality is also the unit rate.

• True
• False

If there is a constant of proportionality in an example, then we say the relationship is PROPORTIONAL

BE CAREFUL: sometimes the relationship is almost proportional but then we say its not because the constant isn't the same for all.

Multiple Choice

Is this table proportional? Look across the table from x to y

• yes

• no

• I'm not sure, I need extra help!

Multiple Choice

Proportional or Non-Proportional? Look vertically from x down to y

• Proportional

• Non-Proportional

Multiple Choice

Is this table proportional?

• Yes
• No

Multiple Choice

Does the table represent a proportional relationship? Look from x to y

• Yes.

• No.

Multiple Choice

Is this table proportional or not proportional

• Proportional

• Not Proportional

Multiple Choice

Is this table proportional or not?

• Proportional

• Not Proportional