Finding Unit Rate
Which is the Better Buy?
Proportional Relationships
Proportional Relationships/slope
Constant of Proportionality
100
Five boxes of cereal cost $20. What is the unit rate of the cereal?
How much will 8 boxes cost.
$4 per box of cereal
$32 for 8 boxes
100
The market is offering two different brands of paper towels. Brand A is offering 12 rolls for $16. Brand B offers 6 rolls for $9. Which is the better buy?
Brand A is $1.33 per roll
Brand B is $1.50 per roll
Brand A is the better buy
100
Sally is going on vacation with her family. In 2 hours they travel 90.5 miles. If they travel at the same speed, write an equation that represents how far they will travel, d in h hours.
d= 45.25h
100
Does this graph show a proportional relationship?
Yes, it is a straight line that passes through the origin.
100
One of these equations has a proportional relationship. Which one is it and what is the constant of proportionality?
y= 200x + 3
y= 500x
y= 3x + 500
What is y= 500x
COP = 500
200
Sue buys 4 dozen doughnuts for $7.25. What is the cost for 9 dozen?
What is $16.29
200
Butcher A is selling 2 pounds of pork chops for $22.50
Butcher B is selling 3 pounds of pork chops for $28
Which is the better buy?
Butcher A $11.25 per pound
Butcher B $9.33 per pound
Butcher B is the better buy
200
Is there a proportional relationship between x and y?
No, there is not.
6/2 = 3
18/3 = 6
54/4 = 13.5
200
Does this graph show a proportional relationship?
No, the line does not touch the origin.
200
The weight of 4 eggs is 120grams. What is the constant of proportionality
COP = 30
300
At the store they are offering a package of meat that is two pounds for $11.50. What would it cost for 7 pounds of meat?
$5.75 per pound so $40.25
300
A store is offering cans of soup from two companies.
Company A sells 2 cans for $7.50
Company B sells 4 cans for $16
Which is the better buy?
Company A is $3.75 for 1 can
Company B is $4 dollars for 1 can
Company A is the better buy
300
Is There a proportional relationship? If so write an equation to represent this relationship. Let C= cost and b= pounds of bananas
Yes,
C = 1.25b
300
Is this a proportional relationship?
No, it is not a straight line.
300
Ann's car can travel 276 miles on 6 gallons of gas.
Write an equation to represent the distance y, in miles that her car can travel in x gallons of gas.
y= kx
How far can she drive on 7 gallons of gas?
y = 46x
y = 46 (7) = 322 miles
400
A first class letter cost $.49 for the first ounce and then $.22 for each additional ounce. What is the cost of a 6 ounce letter?
$.49 x $.22(5) = $1.59
400
You go out for dinner to a restaurant which is having a buffet. However you have to decided between two of them, which one offers the better deal. Restaurant 1 says that for 4 people it would cost $168. Restaurant 2 says that for 5 people the cost would be $190. Which offers the better deal?
Restaurant 1 is $42 per person
Restaurant 2 is $38 per person
Restaurant 2 is the better deal
400
Find the constant of proportionality and write an equation representing the relationship between cups of flour and loaves of bread
k = 1/2 = 0.5
k = 2/4 = 0.5
k = 4/8 = 0.5
k = 5/10 = 0.5
y= 0.5x
400
What kind of slope does this line have?
Zero Slope
400
Which one one of these uses proportional reasoning to solve.
A) Tim is 10 years old when Thomas is 3 years old. How old will Thomas be when Tim is 20?
B) Marco buys cat food and it is 3 bags for $15.75. How much would he spend on 5 bags of cat food?
B
Thomas will be 13 years old.
Marco will spend $26.25
500
A painter mixes 2 1/2 pints of yellow paint with 4 pints of red paint to make a certain shade of orange paint. How many pints of yellow should he mix with 10 pints of red paint to make this shade of orange?
6.25 pints
500
You go to the store looking to buy fish for dinner. When you arrive there are three types of fish each with a different price. Fish A is 2 pounds for $23.50. Fish B is 1 pound for $11 and Fish C is selling 4 pounds for $46.75. Which is the better buy?
Fish A is $11.75 per pound
Fish B is $11 per pound
Fish C is $11.69 per pound
Fish B is the Best Buy
500
Is this relationship proportional? If yes, write its equation.
k = 1212/6 = 202
k = 808/4 = 202
k = 606/2 = 303
k = 1616/8 = 202
No, this relationship is not proprtional
500
What type of slope does this line have and does it show a proportional relationship?
A negative slope
No it is not proportional, it does not pass through the origin.
500
Are the perimeter and sides of a square proportional?
Side length (in) 2 4 6 8
Perimeter (in) 12 24 36 48
What is the equation using the COP y = kx
What would the sides of the square with the perimeter 96
y= 6x
96 = 6x so 96/6 is 16