Sample+text+Ratios

= Section One - Ratios =



The soccer game in the photo gives us a chance to count people, and to compare those counts to each other. For example, there are nine total players shown in this photo. As we begin to compare different sub-groups, however, it becomes more meaningful. Sometimes we use the word "to" as a comparison term. Here are some comparisons that can be made:

Five South China (red) players **to** nine total soccer players Four Ranger (blue) team members **to** nine total soccer players Five South China (red) players **to** four Ranger (blue) team members We compared "red players" to "blue team members" and to "total players", but in reality each of these categories could be described as "soccer players". We were comparing one kind of soccer player to another.

= Ratio : A ratio is a comparison between two things that have approximately the same unit of measurement.=

There are three different ways that you will see ratios written. It is important to see that they are all saying the same thing, but it will obviously be clear that one format is more helpful for doing math with ratios.

An important skill will be translating between these three forms. You will often find the word form, or a colon, in the problem, but will need to translate into the fraction form to do any calculations. If you look at the examples above, you can see how the these three different forms relate to each other.


 * Important**: The quantity that comes first is always the numerator, and the second quantity is always the denominator.


 * Question**: If you are going to compare nuts and bolts, which number goes first, or which is the numerator? Click on the picture to see a detailed answer.



** Let's Try a Few **
Read the following scenario and then answer the questions using ratios is fraction format.



Last year the Old Dominion Logging Company harvested 93,000 Douglas Fir trees and 38,000 Spruce trees from a site in Western Oregon. In an effort to replace the harvested trees, they planted six seedlings for each tree they took - six firs for each fir tree and six spruces for each spruce tree.

1. What is the ratio of Spruce trees to Douglas Fir trees that were harvested?

2. Write the ratio of Douglas Fir trees taken to the total number of trees harvested.

3. What is the ratio of Spruce trees planted to the number of Spruce trees harvested?