Proportional or Not?
From Tables
From Equations
(Using y=kx)
(Using y=kx)
From Graphs
Word Problems
(Remember y=kx)
(Remember y=kx)
100
Does the table represent a proportional relationship or not? Be able to explain your answer.
Not Proportional, when dividing y/x they do not all equal the same constant of proportionality.
100
What is the constant of proportionality?
k = 45
100
What is the constant of proportionality?
y=0.6x
Remember the equation y=kx
k = 0.6
100
The ordered pair on a graph of a proportional relationship is (5, 15). What is the constant of proportionality?
k=3
100
Peter sells shoes. On Monday he sold 15 shoes in 5 hours. On Tuesday he sold 18 shoes in 6 hours. How many shoes does Peter sell in an hour?
3 shoes per hour
200
Does the graph represent a proportional relationship?
If so, What is "k"?
Yes, it is proportional.
k= y/x = rise/run = 1/3
200
What is the constant of proportionality, k?
DAILY DOUBLE: Write an equation that shows the proportional relationship.
k = 12
DAILY DOUBLE: y =12x
200
The community center provides tutoring for students. The cost of tutoring is $18 per session.
Write the equation to model the total cost (C), after (s) sessions.
C = 18s
200
What is the constant of proportionality?
k=5
200
David is making his own strawberry yogurt. He uses 4 cups of milk for every 14 strawberries. Write an equation that represents the situation where y is the number of strawberries and x is the number of cups of milk. (Remember to use y=kx)
y=3.5x, y=(14/4)x
300
Does this graph represent a proportional relationship? Why or why not?
No, it is a straight line BUT it does not go through the origin.
300
How much would it cost for 12 adults to go to the amusement park?
$900
300
What is the unit rate (money earned per hour) if the total pay is $186 for 24 hours?
You may use a calculator if need be.
$7.75 per hour
300
Write and equation that represents the relationship.
y=5x
300
DAILY DOUBLE
A
400
Does this table represent a proportional relationship? If so, what is "k"?
x 2 5 8 10
y 12 30 48 60
Yes, it is proportional and k=6.
400
Raj buys 12 packs of juice boxes that are on sale and pays a total of $48.00. How much will Raj pay to buy 8 more packs of juice boxes at the same store?
HINT: Find k first, then multiply that times how many more packs of juice boxes Raj buys.
$32.00
400
What is the constant of proportionality in the equation: y= 5x
k=5
400
Two points on a graph are (3, 5) and (9, 15). If a line is drawn through these points, does it make a proportional graph? Why or why not?
Yes, it is proportional because 5/3 = 15/9 so you have the same constant of proportionality, k.
400
Which value should represent x (the independent variable) and y (the dependent variable)?
m is the y-value
c is the x-value
500
Week 4: k = $2.49
500
Write 3 different ordered pairs for the following relationship:
y = 7x
Remember that ordered pairs are written like (x,y)
Show Your Answers (may vary)
Ex: (0,0), (1,7), (2,14), (3,21), (4,28), etc.
500
Write a proportional equation where k is a multiple of 4.
Answers may vary.
Ex: y=4x, y=8x, y=20x, etc.
500
Two points on a graph are (10, 35) and (20, 55). If a line is drawn through these points, does it make a proportional graph? Why or why not?
No, it is not a proportional graph because 35/10=3.5 and 55/20=3.75 so they have different k's.
500
First find the unit rate for Brand A and Brand B. Then find the difference in the unit rates.
Difference is 4 cents per ounce