Probability of Compound Events

Today We Discussed:

Today we discussed probability of compound events.  We reviewed what the word "compound" means (and in this case, it simply means more than one), and discussed the different types of compound events.  There are two types:  independent events and dependent events.  Independent events occur when the outcome of one event has no effect on the other (ex:  flipping a coin twice).  Dependent events occur when the outcome of the first event does have an effect on the event that comes after (ex:  taking a card from a deck of cards and keeping it, then taking another card).

The numeric probability of dependent events can be found by multiplying the theoretical probability of each event together.

For two independent events, P(A and B) = P(A) * P(B)
For two dependent events, P(A then B) = P(A) * P(B after A)

Vocabulary: independent events, dependent events

Sections Covered in Textbook:

4-6: Probability of Compound Events

Resources & Tutorials:

1) What are compound events?
2) How to determine if your events are independent or dependent.
3) How to find probability of independent events.
4) How to find probability of dependent events.

Applying Ratios to Probability

Today We Discussed:

Ratios can be used to express everyday activities, and we will be using them in the context of probability.  Probability simply is the chance that an event can occur.  We defined all of the terms associated with both theoretical and experimental probability, and talked about how to find a sample space and how that relates to probability.  Exploring experimental probability is a good way to demonstrate that what we expect to happen, does not always occur, and probability is just based upon how likely something is to occur, not a guarantee it will occur.

We will be investigating experimental probability more thoroughly in the next week.


Graphic Credit:  Online Math Learning

Vocabulary: probability, outcome, event, sample space, theoretical probability, experimental probability 

Sections Covered in Textbook:

4-5: Applying Ratios to Probability (pages 211-217)

Resources & Tutorials:

1) What is probability?
2) What is an outcome?
3) What is a sample space? 
4) How do you find the probability of a simple event?
5) What is experimental probability?
6) Math is Fun - Probability (not a video)

Percent of Change

Today We Discussed:

We continued the topic of percents in the context of percent of change.  We can have a positive percent of change (representing an increase) or a negative rate of change (representing a decrease).  To determine the percent of change, we have to compare how much something changed to its original quantity.  Percent of change is relative to the original value.

Vocabulary: percent of change, percent of increase, percent of decrease

Sections Covered in Textbook:

4-4: Percent of Change (pages 204-209)

Resources & Tutorials:

1) What is the percent of change?
2) How do you find percent of change?
3) How do you determine percent of increase or decrease?

Proportions and Percent Equations

Today We Discussed:

We expanded our discussion of proportions to include the percent proportion.  We deconstructed the word per-cent to mean "out of 100".  We can solve percent problems using a proportion or using a percent equation with the percent expressed as a decimal.

This unit will continue to explore proportions and percents, and we'll take some time to review the conversions of fractions to decimals to percents and vice-versa.  Students will be encouraged to memorize the decimal equivalents of common fractions as a time-saver.  Normally I am not a big fan of memorization, unless it serves a useful purpose - memorizing common concepts (like divisibility rules, the quadratic formula, and common numbers) can be a big time-saver leaving more time for higher order problem solving.

As we continue to explore the relationships among decimals, fractions, and percents, I plan to expand our discussion to other proportions, like circles.  We will investigate some probability in this unit as well.

Vocabulary: percent proportion, percent equation

Sections Covered in Textbook:

4-3: Proportions and Percent Equations (pages 197-202)

Resources & Tutorials:

1) What is a percent proportion?
2) How do you use a proportion to find a whole?
3) How do you use a proportion to find what percent a part is of a whole?
4) How do you use a proportion to find part of a whole?
5) What is a percent equation?
6) More Percent Equation Links

Ratios and Proportions

Today We Discussed:

We began our unit on solving and applying proportions today, and introduced/reviewed some important vocabulary, beginning with ratios.  A ratio is just a comparison of numbers by division.  Students have seen ratios ever since they began working with fractions.  When we talk about rates, we create a ratio of two numbers that have different units.  We have already seen rates this year, when dealing with uniform motion -  rate of speed (comparing a distance with how much time elapses). 

We also used conversion factors to convert rates.  A conversion factor is a rate that is equal to 1 (multiplicative identity states we can multiply by 1 and not change the identity of our number).   For example, a unit conversion would be 60 seconds per minute since 1 minute=60 seconds.

Finally, we used the means-extremes (cross products) property to solve proportions. 

Vocabulary: ratio, rate, unit rate, conversion factor, unit analysis, dimensional analysis, proportion, cross products

Sections Covered in Textbook:

4-1: Ratio and Proportion (pages 182-187)

Resources & Tutorials:

1) What is a ratio?
2) What are rates and unit rates?
3) What is dimensional or unit analysis?
4) What is a proportion?
5) How to solve a proportion by using cross products?

6) Ratio and Proportion Notes

Solving Absolute Value Inequalities

Today We Discussed:

We continued our discussion about absolute value but moved on to inequalities.  Just like absolute value equations, we must consider TWO cases for absolute value inequalities - the positive case and the negative case.  Furthermore, we have to analyze which direction our solutions go based upon whether we are dealing with a greater than absolute value inequality or a less than absolute value inequality.

• Greater than absolute value inequalities function like OR compound inequalities.
• Less than absolute value inequalities function like AND compound inequalities.  

Graphic Credit: http://andymath.com/solving-absolute-value-inequalities/

Sections Covered in Textbook:

3-6: Absolute Value Equations and Inequalities (pages 167-171)

Resources & Tutorials:

1) How do you figure out if you have an AND or OR compound inequality?
2) How to solve an AND absolute value equation.
3) Introduction to Absolute Value Inequalities.
   (Use navigation on the left for more types of examples.)

Solving Absolute Value Equations

Today We Discussed:

We moved into the next section in our book and discussed absolute value equations.  We will tackle absolute value inequalities on Thursday and Monday.

First, we reviewed absolute value and what it means - a number's positive distance from zero.  Absolute value equations add a small level of complexity because when we take the absolute value of a quantity, it will always be positive.   We can have an expression inside the absolute value bars be either positive OR negative, so we can end up with two solutions for the variable in these cases.

We must also analyze whether or not our absolute value equation makes sense.  In most cases, we will get two solutions, but there will be times when no solutions will be possible.  We need to make sure our equation is logical. 

Take for example the equation |x -2| = -3.   

There will never be a case when we take the absolute value of an expression that will result in a solution that is less than 0.  By its very definition, absolute value is always positive.  

For each of these absolute value equations, we will need to consider TWO cases for each solution set:  the positive case and the negative case. We will need to solve TWO equations to get the complete solution for the variable.

Sections Covered in Textbook:

3-6: Absolute Value Equations and Inequalities (pages 167-171)
(We will only cover equations today!)

Resources & Tutorials:

1) Four steps to solve absolute value equations. 
2) Introduction to absolute value equations.
3) Chili Math - Solving Absolute Value Equations (Not a video)

Solving Compound Inequalities

Topics for Today:

Our discussion about inequalities has moved on to compound inequalities.  We discussed the word "compound" and related it to compound words and compound sentences.  There are two types of compound inequalities:

• inequalities using OR 
• inequalities using AND. 

For the OR types, only part of the inequality needs to be true for the entire compound statement to be true.  For the AND types, we must have both parts true at the same time.  OR inequalities can be related to the UNION of two sets, and AND types represent the INTERSECTION (where both criteria are true at the same time).   Venn Diagrams (circle diagrams) are often used as pictorial representations of our sets.  

Graphic Credit:  

https://rstudio-pubs-static.s3.amazonaws.com/282515_ddb4251ce953466fb8055bb4fd4837b9.html

Vocabulary: compound inequality

Sections Covered in Textbook:

3-5: Compound Inequalities (pages 161-165)

Resources & Tutorials:

1) What is a compound inequality?
2) How do you solve an OR compound inequality and graph it?
3) How do you solve an AND compound inequality and graph it?
4) How do you solve an AND compound inequality rewriting it as two?
5) What is a Venn Diagram?
6) Schoolhouse Rock - Conjunctions

Solving Multi-Step Inequalities

Topics for Today:

We continue to build on our problem-solving skills with solving inequalities.  Today we moved on to more complicated inequalities that involve several steps.  Again, we approach these problems just like solving equations, with the first step being to identify the variable.  Once we identify the variable, we need to plan for how we "undo" operations performed on the variable with the goal of getting the variable by itself.  To accomplish this goal, we perform the order of operations (PEMDAS) in reverse.  *Students must always keep in mind that when multiplying or dividing an inequality by a negative number, they must reverse (flip) the inequality sign to keep the truth of the inequality.*

Sections Covered in Textbook:

Solving Multi-Step Inequalities (pages 153-159)

Resources & Tutorials:

1) How do you solve a multi-step inequality?
2) How do you solve an inequality with variables on both sides?
3) How to solve multi-step inequalities.

Solving Inequalities Using Multiplication and Division

Topics for Today:

Our discussion about solving inequalities moved to solving by using the multiplication and division properties of inequality.  We solve inequalities using the same steps and procedures as solving equations, but there is one notable exception.  For cases when we either multiply or divide both sides of our inequality by a negative number, we must switch the inequality sign to preserve the truth of the inequality.  To illustrate why this works, we did a little exploration with simple inequalities in class to help understand why the "truth" of an inequality changes.

Vocabulary: multiplication property of inequality, division property of inequality

We considered the following examples in class:

Sections Covered in Textbook:

3-3: Solving Inequalities Using Multiplication & Division
       (pages 146-151)

Resources & Tutorials:

1) What is the division property of inequality?
2) What is the multiplication property of inequality?
3)  Solving inequalities using multiplication and division
4) Virtual Nerd Page with more tutorials.

Solving Inequalities Using Addition and Subtraction

Topics for Today:

Now that we understand what inequalities and solutions to inequalities are, we can now move into solving them.  When solving simple inequalities using addition and subtraction, we basically follow the same steps we use for solving simple equations.  For these problems, we will use the addition and subtraction properties of inequality to "undo" operations performed on a variable with the goal of getting the variable by itself.  Checking solutions to inequalities may not always locate our mistakes since there are an infinite number of possible solutions we can use to check ourselves.  Students will be encouraged to try out multiple possible solutions when checking.

Vocabulary: equivalent inequalities, addition property of inequality, subtraction property of inequality.

Graphic Credit:
https://www.mathwarehouse.com/number-lines/graph-inequality-on-number-line.php#examples1

Sections Covered in Textbook:

3-2: Solving Inequalities Using Addition and Subtraction (pages 140-144)

Resources & Tutorials:

1) What is the addition property of inequality? 
2) How do you solve an inequality using subtraction?
3) How do you solve an inequality using addition?

    (This includes putting the solution in set notation, which we did not discuss in class.)

Inequalities and Their Graphs

Topics for Today:

We moved on to Chapter 3 today.  Our discussion has moved from equations where both sides are equal, to inequalities where one side is larger or smaller than the other.  We also discussed the difference between solutions where the endpoint is included vs excluded and explored the graphs of inequalities.  A solution to an inequality is any value that will make the inequality true.  Inequalities differ from equations because inequalities often have infinite solutions that are bound by a particular value whereas equations typically have a finite solution set.

Graphic Credit: https://www.katesmathlessons.com/graphing-inequalities.html

Vocabulary: inequality, solution to an inequality

Sections Covered in Textbook:

3-1: Inequalities and Their Graphs (pages 134-138)

Resources & Tutorials:

1) What is an Inequality?
2) How Do You Graph Inequalities?
    (This video also includes infinite sets which we did not discuss.)

Literal Equations

Topics for Today:

Today we continued our exploration of equations, but focused on literal equations and formulas.  Literal equations are just equations that have more than one variable.  Formulas are mathematical or scientific facts, rules, or relationships expressed with mathematical symbols.  Students have been using formulas for much of their mathematics studies, although they may not be aware.  Earlier in this chapter, we used the formula for distance (d=rt) and also perimeter of a rectangle {P=2(l+w)}.

We can use our knowledge of solving equations to move variables around in literal equations or formulas, to solve for a particular variable.  The properties of equality (addition, subtraction, multiplication, division and distributive) still apply here in these examples.

The first step in any solving equation problem it to identify the variable that you are solving for.  Once that is done, we follow the reverse order of operations to isolate the variable, and follow the same steps we used for solving multi-step equations.  As a reminder, here are those steps again:

Vocabulary: formula, literal equation

Sections Covered in Textbook:

2-6: Formulas (pages 111-114)

Resources & Tutorials:

1) What is a literal equation?
2) How do you solve a formula for a variable?
3) Summary of solving literal equations.

Equations and Problem Solving Part 2 - Uniform Motion

Topics for Today:

We continued our discussion about problem solving by investigating uniform motion problems.   Most students are familiar with the basic formula for motion: 
distance = rate * time, or in algebraic terms, d = rt.

Uniform motion problems fall into three main categories: same-direction travel, round-trip travel, or opposite-direction travel.  Depending upon what the problem is asking, we'll combine our problem data in different ways to find our answer, but in each case, we will still apply the general formula (d=rt) to set up our problem.

Drawing diagrams to help picture what is going on in the problem is another helpful strategy.  Using a table to solve problems helps organize all the supporting data, and provides a systematic way to solve more complex problems.  Students are encouraged to use a table and to draw a picture of what is going on in the question to help better understand what is being asked.

Sections Covered in Textbook:

2-5: Equations and Problem-Solving Part 2 (pages 103-110)

Resources & Tutorials:

1)  How to Solve Opposite-Directions problem.
2)  How to Solve Same-Directions problem.
3)  How to Solve Round-Trip Travel Problems.

Equations and Problem Solving Part 1

Topics for Today:

Now that we know how to solve all types of equations, we will use that knowledge to solve story problems.  There are many different types of story problems, but most of them can be categorized into one of several categories.  Today's lesson will focus on problem solving involving defining variables in terms of each other,  consecutive integers (which also involves defining variables in terms of another), and break-even problems.

Vocabulary: consecutive, break-even

Sections Covered in Textbook:

2-5: Equations and Problem Solving (pages 103 - 110)
We will continue working on this topic tomorrow with more examples.

Resources & Tutorials:

1) Solving Break-Even Problems
2) How to find the Break-Even Point
3) Solving Word Problems with Consecutive Integers

Solving Equations with Variables on Both Sides

Topics for Today:

Our discussion about solving equations moved on to situations where there are variables on both sides of an equation.  The basic properties of equality still apply when dealing with variable terms.  We used the addition, subtraction, multiplication, and division properties of equality to get variables on one side, and constants on the other side of the equation.  For equations with variables on both sides, it is possible for the equation to have infinitely many solutions (identity) or no solution at all.  Students will need to be on the lookout for these special cases, which show themselves is interesting mathematical ways.

Sections Covered in Textbook:

2-4: Equations with Variables on Both Sides (pages 96-100)

Resources & Tutorials:

1) Solving Equations with Variables on Both Sides
2) Solving Equations with Variables on Both Sides and Grouping Symbols

Solving Multi-Step Equations

Topics for Today:

We moved on from two-step to multi-step equation solving.  Today's lesson focused on simplifying with grouping symbols, and multiplying through to eliminate fractions and decimals to make the equation easier to solve.

Sections Covered in Textbook:

2-3: Solving Multi-Step Equations (pages 88 - 93)

Resources & Tutorials:

1) Solving Multi-Step Equations using Distributive Property
2) Solving Multi-Step Equations by Clearing Fractions

Solving 2-Step Equations

Topics for Today:

Our discussion about solving equations moved on to solving 2-step equations.  The order of operations still figures in to this process, although since we are undoing operations, we go in reverse.

Sections Covered in Textbook:

2-2: Solving Two-Step Equations (pages 81- 86)

Resources & Tutorials:

1) How do you solve a 2-step equation?
2) Math Antics - How to solve 2-step equations.

Solving 1-Step Equations

Topics for Today:

Today we reviewed solving one-step algebraic equations.  We discussed what inverse operations are, and also defined the term solution.  Students are reminded that all they are accountable for all the mathematics that came before this class, as well as any new learned material.  Mathematics is a cumulative subject, and the skills built in the past will continue to be used to solve new problems.  That means that we will continue to integrate fraction and decimal operations into our problem solving.  Equation operations will include all types of real numbers.

Sections Covered in Textbook:

2-1: Solving One-Step Equations (pages 74-79)

Resources & Tutorials:

1) Math Antics - How to Solve a 1-step Equation.
2) How to solve an equation using addition.
3) How to solve an equation using subtraction.
4) How to solve an equation using multiplication.
5) How to solve an equation using division.
6) How to solve a decimal equation using subtraction.
7) How to solve an equation when multiplying fractions. 

Chapter 1 Review

Topics for Today:

Today we played a game of Money Grab to finish up our review of Chapter 1.  Students should make sure their binders are fully organized prior to joining class on Thursday.  Binders will be collected at the beginning of class.  For a list of topics that need to be in the notebook, open the Chapter 1 Table of Contents Google Docs that I have shared with you from the Chapter 1 folder.  

Topics covered in Chapter 1:  Using variables, order of operations, classifications of real numbers, real number operations (adding, subtracting, multiplying, and dividing), as well as the properties of equality.  

Sections Covered in Textbook:

Chapter 1:  Tools of Algebra (pages 4-58) - Omit section 1-9

Resources & Tutorials:

Properties of Real Numbers Days 1 & 2

Topics for Today:

Today we laid the groundwork for all the properties of real numbers, and we'll be taking two days to discuss and master them.  The properties are a set of truths that act as rules to allow us to rewrite numbers and equations to make them easier to solve.  We also use the properties to justify the different steps we take to simplify expressions and solve equations.  Students also made a set of notecards that can be used during any quiz or test this year.

This is the last section of this chapter.  I have posted a Chapter 1 Review on Delta Math for those who want more practice.  This assignment is optional but highly recommended.  

Sections Covered in Textbook:

1-8: Properties of Real Numbers (pages 54 - 57)

Resources & Tutorials:

1)  Video page for the addition, subtraction, multiplication and division properties.
2)  What is the substitution property of equality?
3)  Summary sheet of Properties from Math-Aids.

The Distributive Property

Topics for Today:

Today we discussed the distributive property  of multiplication over addition and subtraction.  We also used the distributive property to multiply large numbers using mental math.  We also discussed how to combine algebraic like terms, and expanded our algebra vocabulary.  We revisited translating phrases into algebraic expressions with the addition of the distributive property.

Vocabulary: constant, like terms, distributive property, coefficient, term

Sections Covered in Textbook:

1-7: The Distributive Property (pages 47 - 52)

Resources & Tutorials:

1) What is the distributive property?

Multiplying and Dividing Real Numbers

Topics for Today:

Earlier this week we took our first quiz of the year.  How did it go?  Did you properly prepare?  If not, what improvements can you make for the future?  Students will be allowed and expected to complete quiz corrections for partial credit.  Quizzes are meant as assessment and learning tools.  Students should always be asking, "How can I do better?".

We moved on to multiplying and dividing real numbers today.

Some basic sign rules for multiplication and division:

+ · + = +      + / + = +
+ · - = -      + / - = -
- · + = -      - / + = -
- · - = +      - / - = +

Vocabulary: Identity property of Multiplication, Multiplication Property of Zero, Multiplication Property of -1, Inverse Property of Multiplication, multiplicative inverse, reciprocal

Sections Covered in Textbook:

1-6: Multiplying and Dividing Real Numbers (pages 37 - 44)

Resources & Tutorials:

1) How do you multiply and divide numbers with different signs?
2) What are Multiplicative Inverses?
3) What is a reciprocal?

Subtracting Real Numbers

Topics for Today:

We continued our discussion of adding real numbers (both positive and negative) using a number line and integer chips.  Our rules for addition are:

• If the signs are the same, add and keep the sign.
• If the signs are different, subtract and keep the sign of the number with the larger absolute value.  

Stated another way...

Subtraction is actually the addition of opposites!  

For subtraction problems, first change to addition by adding the opposite, then follow your addition rules!  

                  6 – 10 =

              6 + (-10) =  

Subtract 6 from 10 and keep the negative sign because |-10| > |6|

Therefore, the answer is – 4. 

Sections Covered in Textbook:

1-4: Adding Real Numbers (pages 24-31)
1-5: Subtracting Real Numbers (pages 32-36)

Resources & Tutorials:

1) How do you add two negative numbers?
2) Rules for Adding Integers
3)  How to rewrite a subtraction problem as addition