Recognising and representing proportional relationships between quantities

What is a CONSTANT OF PROPORTIONALITY

• A constant ratio or unit rate of 2 quantities

• A comparison between two quantities

• The relationship between two ratios with a constant rate or ratio

• The relationship between 1 unit of quantity to another

 $\frac{4}{9\ }=\frac{24}{x}$  

• x=10

• x=10.6

• x=54

• x=78

Justine buys a container of 30 ring pops for $15. What is the constant of proportionality for the cost of 1 ring pop?

The cost to get into Holiday World and Splashing Safari was $90.00 for 3 people. Find the constant of proportionality and describe what it means in this situation.

• k = 30, 30 people per dollar

• k = 0.03, 0.03 people per dollar

• k = 30, 30 dollars per person

• k = 0.03, 0.03 dollars per person.

Betty paid $11.25 for 3 kids meals when she went through the drive thru. What is the constant of proportionality for the cost of each meal?

 $\frac{7}{8}\ =\ \frac{21}{?}$  

• 3

• 24

• 14

• 4

Janet used 155 beads to create 5 necklaces. What is the constant of proportionality? (How many beads did she use to make each necklace?)

• 31

• 775

• 155

• .032

What is constant of proportionality?

• A number that shows the proportional relationship between two amounts (x and y)

• when two quantities are always in equivalent ratios

Solve for x 

• x = 28

• x = 26

• x = 1/26

• x = 16

Solve the proportion.

• 1
• 3
• 6
• 5