Lesson 1
What is the definition of a ratio
An ordered pair of numbers which are not zero.
(Alternative definitions acceptable)
How can you tell if a table of values is proportional?
If the constant relating x and y stays the same for the entire table.
Is 3/12 proportional to 5/20? If so, find the constant
Yes, the constant is 4.
Is the graph Ms. K holding up proportional? Why or why not?
No. Not a straight line or going through the origin.
Bananas cost $0.59 per pound. Write an equation for the constant of proportionality.
y = 0.59x
(Equivalent equation acceptable)
What is the definition of a unit rate.
The numerical value of a ratio.
(Alternative definitions accepted)
If you make $28 in one hour, how much money will you make after 5 hours?
$140 in 5 hours
Is 4/17 proportional to 5/19? If so, what is the constant?
No it is not
Is the graph Ms. K is holding proportional? Why or why not?
Yes, straight line through the origin
It costs $3 to dry clean 18 pairs of pants. Write an equation for the constant of proportionality.
y = 6x
(Equivalent equations acceptable)
Which unit rate represents a faster speed? 2.5/1 or 1.2/1
2.5/1
The bigger the unit rate, the faster the speed because it represents more being accomplished in one unit.
If you make $11 in one hour, how many hours will you have worked if your check is $275.66
25.06 hours
Is 12/8 proportional to 3/2? If so, what is the constant?
Yes, the constant is 2/3.
(Alternative identifiers accepted)
Is the graph Ms. K holding proportional or not?
No. Straight line but doesn't go through the origin
For every $5 that Micah saves, his parents contribute $10. Write an equation for the constant of proportionality.
y = 2x
(Equivalent equation acceptable)
Find the unit rate: 360 miles in 9 hours
40 miles in 1 hour
If you burn 12 calories for every minute of jump rope, how many calories will you burn after 7.5 minutes of jumping rope?
You would burn 90 calories
If 6 ounces of coffee cost $2.10, what will a bag of coffee that weighs 20 ounces cost?
A 20 ounce bag will cost $7
Why is it important for a proportional relationship to pass through the origin?
Because your constant has to remain the same for all values for x, including zero.
(Alternative responses accepted)
Jennifer is shopping with her mom. They pay $2 per pound of tomatoes. Use the equation for the constant of proportionality to find how much money they will spend if they need 4 pounds of tomatoes.
y = 2x
They will spend $8.
Find the unit rate: 40 meters in 16 seconds
2.5 meters in 1 second
If you get a job working at a restaurant and you work for zero hours, how much money would you make?
You would make zero dollars
Is 6/2.10 proportional to 8/2.8? If so, what is the constant?
Yes, the constant is 0.35.
What are the TWO characteristics of a proportional graph?
A student can run 10 laps in 25 minutes. Use the equation for the constant of proportionality to find how many laps can that student run in an hour.
y = 0.4x
The student can run 24 laps in one hour.