Vocabulary
Define a Ratio
A comparison of two quantities that may or may not include units.
Write the ratio of 6's to 7's.
6 6 6 7 7 7 7
3:4
Given the rate 18 miles per 6 gallons, find the unit rate.
3miles per gallon
Do these ratios form a proportion?
3.5 to 2 and 14 to 8
Yes
Write the ratio of the total to the &'s.
& & & * * # # #
8 to 3
Define a Rate
A rate is a ratio of two quantities using different units.
List two equivalent ratios to 4:5
8:10, 12:15, etc.
Are the following rates equivalent?
15 breaths for every 36 seconds
90 breaths for every 3 minutes
No
Use cross products to solve this proportion.
5/7 = x/21
x=15
When looking at a graph on the xy-plane, how do you know what the constant of proportionality is? Use the easiest method.
Find the y-value when x=1.
Define a Proportion.
A proportion is an equation stating that the values of two ratios are equivalent.
Describe the differences between ratios and fractions.
A ratio can compare quantities of two different units, while a fraction can only compare within one unit.
A ratio can be part-to-part as well as part-to-whole, and vice versa, but a fraction can only be part-to-whole.
What are the two main systems of measure commonly used?
US Customary system (Imperial System)
Metric System
Use cross products to solve this proportion.
6/p = 42/35
p=5
True or False?
The graph of the equation y=kx, where k is the constant of proportionality, always runs through the point (0,0).
True
Define the Constant of Proportionality.
The number that represents the multiplicative relationship between the quantities x and y. Usually it is represented by the letter k. The relevant equation is y=kx, and the relevant ratio is k=y/x.
A bag contains red marbles and blue marbles. There are 18 red marbles in the bag. The ratio of red marbles to blue marbles is 6 to 9. How many blue marbles are in the bag?
27
Given the conversion factor 1ft/12in, convert 4 feet into inches.
48 inches
Find the value of x so that the ratios are equivalent.
x to 0.25 and 6 to 1.5
x=1
List all the ratios you can write about the following:
w w w w w t t t
5:3, 3:5, 8:5, 5:8, 3:8, 8:3
Define the Scale Factor
The value of the ratio that describes the multiplicative relationship between the dimensions of a scale drawing or scale model and the dimensions of the actual object.
Fill in the following blanks in the ratio table.
Flowers: 1 2 4 _
Petals: 5 _ _ 15
Flowers: 1 2 4 3
Petals: 5 10 20 15
Convert 1 mile per 4 minutes into feet per seconds.
22 feet per 1 second
Tell whether x and y are proportional.
x: 0 1 2 3
y: -2 1 4 7
No.
Tell whether x and y are proportional. If so, identify the constant of proportionality.
x/y=2
Yes...