Vocabulary
An equation stating that two ratios are equal.
Proportions
An ice cream shop charges $2 for 1 topping and $5 for 3 toppings. Is the price proportional to the number of toppings?
No
Sam sends 18 emails in 6 minutes. What is the unit rate of emails per minute
3 emails per minute.
Determine the better buy and the unit price: Quick Picker-Upper sells 6 rolls for 6.69 Easy Wipe sells 11 rolls for $12.00.
Easy Wipe. $1.09 per roll
Write in simplest form: 40 to 36
10 to 9
What do we know about a unit rate?
The 1 is always at the bottom
These are two requirements for a graph to represent a proportional relationship
straight line and through the origin
Toby can bake 24 cookies with 4 cookie trays and 54 cookies with 9 cookie trays. What is the constant of proportionality
6
Determine better buy and unit price: a six-pack of soda for $1.50 or an eight-pack for $2.40
the six-pack of soda. $.25 per can
Write in simplest form: 48 to 9
16 to 3
A comparison of two quantities by division (X/Y or X:Y-- numerator associate with word "to" and denominator "of"
Ratios
A factory can produce 20 iphones in 60 minutes, 50 iphones in 150 minutes and 4 iphones in 12 minutes. Is this a proportional relationship?
yes, 1 phone takes 3 minutes.
Rosie gives out 120 treats to 8 dogs. How many treats does each dog get?
15 treats per dog
Determine better buy and unit price: Louis purchases three pairs of socks for $1.99 and Mary purchases four pairs of socks for $2.40.
Mary's purchase of four socks. $.60 per pair of sock
Write in simplest form: 90 to 60
3 to 2
The comparison of two equal ratios or the relationships between two equal ratios.
Proportional Relationship
Trey is observing the growth of a sunflower. After 1 day its height was 2 inches, after 4 days the height was 10 inches, and after one week the height was 2 feet. Is height proportional to amount of days?
No
Kelly spends $6.75 for 9 jolly ranchers. How much does one jolly rancher cost?
$0.75 per jolly rancher
Which is a better buy and what is the unit rate? Danica buys 15 gallons of gas for $22.49 or Damian buys 20 gallons of gas for $26
Damian. It is $1.30 per gallon of gas.
Write in simplest form: 52: 18
16 : 3
the constant value of the ratio of two proportional quantities x and y
Constant of Proportionality
A 12 oz box of crackers is $2.08, while a 16 oz box costs $2.99. Is price proportional to size? If yes, what is the unit rate, if not, which is the better buy?
Not proportional, the 12 oz box is a better buy ($.17/oz)
A jeep can drive 192 miles on 6 gallons of gas, and 448 miles on 14 gallons of gas. Using the constant of proportionality, how many miles could he drive on 10 gallons of gas?
320 miles
Determine the better buy and the unit rate: Nikki buys seven new fish for $59.96 George buys 10 fish for $90.00
Nikki. $8.57 per fish.
Write in simplest form: 63 to 60
21 to 10