Unit 4

Out_of_proportion
Farmer Smith failed the proportion unit in Algebra.



In Unit 4 we will be covering the concepts of ratios/proportions, and analyzing data.

4.1 is about Using proportional reasoning. Proportions and ratios are two of those math topics that will follow you for the rest of your life. We actually do use them in real life. Whether you are cooking/baking, or dealing with money, or drawing, proportions are very important.


Some vocab:
ratio- a comparison of two quantities that uses division.
proportion- a statement of two equal ratios.
means- In the proportion a:b=c:d, b & d represent the means
extremes- In the proportion a:b=c:d, a & d represent the extremes

Here are the notes for Section 4-1.



A true proportion is one in which the product of the means is equal to the product of the extremes or a(d)=b(d)

Similar figures are geometric figures that have the same shape, but not necessarily the same size. If the similar figures are polygons, then their vertices can be paired in such a way that corresponding angles are congruent and corresponding sides are proportional.



similar1.jpg
These triangles are similar. Their corresponding sides are in the proportion 2:1




Also in Unit 4 we learn how to use a percent as a proportion. There are two ways to solve a percent problem. You can set up the percent as a proportion or solve it by setting up an equation. Remember that a percent is nothing more than a ration of some number over 100. With that in mind you can set up the proportion.

Here are the notes on Section 4-2.

As we continued the unit we talked about how to find the probability of an event to occur.

Remember that the probability of an even to occur has to be anywhere from 0 to 100% or a ratio between 0 and 1.
We did an experiment in class to find the probability of rolling a 7 on a pair of dice and then rolling an odd number on the same dice. We calculated the class probability by totaling the number of rolls and finding out how the sum of each groups favorable outcomes.

At the end, I talked about the difference between accuracy and precision.


accuracy_precision.gif
Here are the notes for Section 4-3--------------> If you need any extra practice with section 4-3 you can click here and download a practice sheet---------> Section 4-4 was about Measures of Central Tendency. These were the:1. Mean- average 3. Mode- Number that occurs most often4. Range- Span of numbersWe also learned how to make a frequency table and how to find the measures of central tendency from the frequency table. Work on this practice worksheet in your notebooks-------->
In Sections 4-5 and 4-6 we talked about how to display our data in various types of graphs and charts. We learned how to make a frequency table, how to create an accurate circle graph/pie chart, how to make a stem-and-leaf plot, as well as how to make a box-and-whisker plot.
These charts might help jog your memory as to what the different charts/plots/graphs look like.


frequency_table
This is your basic frequency table.

boxandwhisker
Box-and-whisker plots help show how data is distributed.

PieChart.gif
Pie charts allow you to compare elements by percents.