Identifying the Constant of Proportionality

The video tutorial explains the concept of proportional relationships and the constant of proportionality, represented by 'k'. It covers how to identify this constant using tables, graphs, and word problems. The tutorial provides examples, such as babysitting earnings, car travel, apple picking, soap costs, gum purchases, and donut pricing, to illustrate how to calculate 'k' and form equations like y = kx. The video emphasizes the importance of the multiplicative relationship between variables in proportional relationships.

What symbol is used to represent the constant of proportionality?

• C

• K

• Y

• X

What does the constant of proportionality tell us in a proportional relationship?

• The ratio of Y to X for all points in the relationship

• The difference between each X and Y value

• The product of all X and Y values

• The sum of all X and Y values

How do you find the constant of proportionality from a table?

• Add Y to X

• Divide Y by X

• Subtract X from Y

• Multiply Y by X

What is the constant of proportionality if 4 hours of babysitting earns $48?

• 4

• 8

• 24

• 12

What equation represents a proportional relationship where K is 55?

• y = 55 + x

• y = x - 55

• y = x/55

• y = 55x

In a graph, how do you determine the constant of proportionality?

• Divide Y by X using any ordered pair

• Multiply X by Y using any ordered pair

• Subtract Y from X using the first ordered pair

• Add all X values and divide by total Y values

What does a constant of proportionality of 4 in a graph indicate?

• For every 4 increases in X, Y increases by 1

• For every 1 increase in X, Y increases by 4

• For every 4 increases in X, Y decreases by 1

• For every 1 increase in X, Y decreases by 4

How do you find the constant of proportionality in word problems?

• Find the sum of Y and divide by X

• Find the product of X and Y

• Divide Y by X to find the unit rate

• Multiply X by the total number of items

What does a constant of proportionality of 0.20 in a word problem indicate?

• For every 20 units of X, Y increases by 1 cent

• For every 1 unit of X, Y decreases by 20 cents

• For every 20 units of X, Y decreases by 1 cent

• For every 1 unit of X, Y increases by 20 cents

If 2 dozen donuts cost $18, what is the constant of proportionality?

• 0.75

• 1.50

• 3.00

• 0.25