RATIOS AND PROPORTIONS
Ratios are the mathematical way to compare one thing to another. It could be as simple as comparing how many girls there are to boys in your class. Here are some definitions to know...
- Ratios: A comparison of two quantities
- Unit Rate: A special ratio that has 1 as its second term
Another important thing to keep in mind: "per"
The word "per" is used often when describing ratios. For example- "A dollar PER ounce". This is also a unit rate.
If I am describing the number of boys and girls in my class, I might say something like..
"There are 4 girls for every 5 boys in our class"
An example representing this scenario is 12 girls and 15 boys in the class.
How would you reduce 28:7 to a unit rate?
First, you would find their common factor. The common factor of 28 and 7 is 7.
Then, you divided each by the common factor. You can think of the common factor as the "magic number".
If you divide 28 by 7, you get 4. If you divide 7 by 7, you get 1.
This means that the unit rate is 4:1.
If I am describing the number of boys and girls in my class, I might say something like..
"There are 4 girls for every 5 boys in our class"
An example representing this scenario is 12 girls and 15 boys in the class.
How would you reduce 28:7 to a unit rate?
First, you would find their common factor. The common factor of 28 and 7 is 7.
Then, you divided each by the common factor. You can think of the common factor as the "magic number".
If you divide 28 by 7, you get 4. If you divide 7 by 7, you get 1.
This means that the unit rate is 4:1.