Today during class we did our "Pre-test" for our current unit of probability. The pre-test prepares us for our upcomming unit test which takes place tomorrow March 19. The format of our pre-test was 2 multiple choice questions, 2 short answer questions, and 1 3-step problem. We were given about 35-40 minutes to write our pre-test and after that Mr. K split us up into groups to compare answers. After about ten minutes of comparing answers, Mr. K went over the questions and showed us step by step how it came out to the answer.
In my group there were a couple a questions that stumpted my group members and I, but now I understand why and how we got the answer.
Here is one question that we didn't quite get right..
Using the word FOOD, find the probability that an arrangement of this word will begin with the two O's if all the letters are used. Correct to the nearest hundreth.
So to start off, you need to make sure that the two O's are stuck together at the front of the four letter combination. A way that Mr. K would refer it to would be "take the two O's and put them in a bag."
And this is what the 4 letter word combination can look like..
The first 1 stands for the 2 O's which are "stuck together," they are first because the question requires for them to be at the front of the four letter combination. The 2 stands for the choice of either F or D. And the last 1 stands for the left over of the previous two. (Say I choose F for the second space, then the last space would be a D and vice versa.)
So now you are required to multiply 1 by 2 by 1 in order to find out the number of ways for the combination. The answer is 2.
Now you take the the amount of ways that the four letter word can be rearranged(2 differnt ways) and you divide it by 4 factorial(representing the total number of letters) divided by 2 factorial(representing the 2 O's)
You would do it like so..
The result would be 2/12 then would reduce into 1/6, and because the question says around to the nearest hundreth, you must express the faction into a decimal which is 0.17.
* JUST A REMINDER * our unit test is tomorrow!
For further review Mr. K posted up extra questions.
I choose Kayla for the next scribe!
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Wednesday, March 18, 2009
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Today's Slides: March 18
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Darren Kuropatwa
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Tuesday, March 17, 2009
Hi everybody, just a heads up there is a pre-test tomorrow so be prepared.
Any who today in class we learned two new topics. These topics are called Mutually exclusive and Non Mutually exclusive events. The way something can be mutually exclusive is if it is impossible for them to occur together. Basically like saying you can't be the age 31 and at the same time be 16, there is just no way. Or like saying can you roll a die and get both a positive and negative number at the same time.
Examples
Drawing one card either, a black ace or a red two
When randomly selecting two animals from a barn either a, cat or dog
Randomly selecting a person either a, girl or a boy
Now non mutually exclusive events are the exact opposites when things can happen together, like either drawing from a deck of cards a king or a spade. You can actually draw a king of spades.
Examples
Selecting a person for your basketball team who is either, fast or tall
Sleeping with either a, long pillow or comfy pillow
Rolling a two dice and either getting a sum of an odd number or a double
Although you may just think of this as the exact opposite to mutually exclusive events there is more thinking involved. Mutually exclusive event formula is (A) n (B) = zero set, done. For non mutually exclusive events there is a big formula you have to follow.
Using Mr.K's example I will explain
You wish to draw either a king or a spade from a single deck
A represents kings
B represents spades
Now remember one card is both keep this in mind
So the formula looks like this P ( A U B ) = P(A) + P(B) - P(AnB)
Plug in the numbers and you it looks like
P ( A U B ) = 4/52 + 13/52 - 1/52
= 1/16
WHOA, why did we subtract the 1/52 people may ask, reason being because the card gets counted so we want to subtracted it so that it doesn't get counted twice.
So that is what we learned in class what I recommend doing is try to make up your own mutually and non mutually exclusive events and practise further with the formula. Now the next scribe I choose is IRIS......
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henson
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Today's Slides: March 17
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Darren Kuropatwa
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Monday, March 16, 2009
Today's Slides: March 16
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Darren Kuropatwa
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Sunday, March 15, 2009
Today in class Mr. K started off by putting us into groups. We were then given problems to solve. You can check the slide for today.
Independent and Dependent event
My understanding about Dependent Variable it's called dependent variable because it's distribution of values depends upon the distribution of the other values or in other words It is something that depends on other factors while Independent Variable is a variable whose value determines the value of other variables or it is a variable that stands alone and isn't changed by other variable.
Here are some examples
The two events do not affect each other because it is an Independent event.
Two balls are drawn successively without replacement from a box which contains 4 blue balls and 3 red balls.
Find the probability that:
(a) the first ball drawn is blue and the second is red
(b) both balls are red.
P(blue) = 4/7
There are 6 balls left and out of those 6, three of them are red. So the probability that the second one is red is given by:
P(red) = 3/6 = 1/2 reminder always simplify
dependent event so 4/7 × 1/2 = 2/7
Also dependent event. Using same method, but realizing there will be 2 red balls on the second draw, we have:

The next scriber I choose is : HENSON
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MAC
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Friday, March 13, 2009
Today's Slides: March 13
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Posted by
Darren Kuropatwa
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12:26 PM
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Labels: Mr. Kuropatwa, Pi Day, Probability, Slides
Thursday, March 12, 2009
Today in class Mr.K started off by putting us into groups. We went over the homework that was assigned to us the night before. The answers to the questions are posted on todays slides, March 12th.
The new lesson we learned today was COMBINATIONS ( the "choose" formula). The formula is as follows:
"n" is the number of objects availabl to be arranged
"r" is the number of objects tht are being arranged
EXAMPLES:
You would read this as 10 "choose" 5 equals 10 divided by 5 factorial multiplied by 5 factorial.
By choosing 5 people to make a team which equals 5!, that means there is remainder of 5 other people from the 10.
The answer to this question is : 252
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Today's Slides: March 12
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Darren Kuropatwa
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4:35 PM
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Wednesday, March 11, 2009
Today in class we started off being broken down into groups. We then quickly checked our homework. We were then given a problem to solve, it's on the slides today March 11, slide 9.
The question was:
Suppose that, when you go home from school, you like to take as great a variety of routes as possible, and that you are equally likely to take any possible route. You will walk only east or south.
We used the Pascal's Triangle to solve how many ways we can get from School to home. The answer was 180 ways to get from School to Home.
This is how it was done:
Then we went into more depth of the question, Daniel went up and explained that there was really only a certain way to go home AND pass the post office. This is what he means. The red lines shows how many ways you can pass the post office, from school to home. The blue just shows the extra routes going from school to home, WITHOUT passing through the post office.
So now getting back to the question which was, what is the probability of passing the post office on your way home.
The answer would be:
Number of ways from School to Home passing the post office: 72
Over the total number of ways from School to Home: 180
SO: 72 / 180 would be the probability of passing through the post office on your way home!
Reminder, always reduce fractions if possible!
Reduced fraction = 2 / 5
And the next scribe would be..
DON !
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Kyle
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9:38 PM
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Today's Slides: March 11
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Darren Kuropatwa
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Tuesday, March 10, 2009
Today's Slides: March 10
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Posted by
Darren Kuropatwa
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4:30 PM
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Examples:
Book
Since there are 4 letters and 2 letters that are the same the equation would be 4!/2! = 12
Mississippi
Since there are 11 letters and 4S's, 4I's, 2P's, the equation would be 11!/(4!*4!*2!) = 34650.
Non distinguishable object is an easier way of solving problems. We didnt really get to look into it a lot so Mr. K said we would do some more tomorrow !
The next scriber would be....
KYLE ! =)
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kathrine
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Monday, March 9, 2009
Today we started off with talking about PI DAY. We get to party this Friday & eat PIE! Not only are we going to eat pie but we get to share math jokes. So everyone don't forget to bring pie along with a stupid math joke.
Our lesson for today was Permutations (the 'Pick' Formula). A permutation is an ordered arrangement of objects.
n - # of objects available to be arranged
r - # of objects that are being arranged
Factorial notation is really an easier way of multiplying all the natural numbers from a particular number down to 1.
We went over our homework as well which are posted on the blog.
Kathrine already knows she's the next scriber.
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Camilla
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5:50 PM
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Today's Slides: March 9
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Posted by
Darren Kuropatwa
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12:31 PM
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Friday, March 6, 2009
Counting
Hello everyone! For today's class we started off with Mr. K teaching us how to count in bases.
Posted by
alvina
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8:37 PM
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Today's Slides: March 6
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Darren Kuropatwa
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Thursday, March 5, 2009
The Fundamental Principle of Counting
Overview of Today
We started off today's class taking a quick look at the blog and then discussed the Bento picture (The first Slide for today). We discussed different ways to arrange the three vegetables in the yellow dish (came to the conclusion it was six). After that we reviewed the homework for last night, and moved on to The Fundamental Principle of Counting.
The Fundamental Principle of Counting
The Fundamental Principle of Counting states: If there are M ways to do a first thing and N ways to do a second thing then there are M x N ways to do both things (found on slide 7).
For Example:
You need to run your weekly errands and need to make a stop at a mall, a grocery store and a hardware store. In your area there are two malls, three grocery stores and two hardware stores approximately the same distance from your house. How many different possible routes are there that include stopping at one of each store.
First pick out the given information:
2 Malls
3 Grocery Stores
2 Hardware stores
Then multiply:
2 Malls x 3 Grocery Stores x 2 Hardware Stores
=12 Different Routes
For more practice:
http://regentsprep.org/regents/Math/counting/praccnt.htm
This site contains simple questions and explanations.
Important Things to Know:
Today there was not a great number of people who completed their homework and Mr. K was not thrilled. He has implemented Homework Quizzes. Mr. K will be checking our homework from a past date so it is important that we date our work as well as label the questions properly. The quiz will just be to hand in the question when it is asked.
There are a couple homework questions at the end of the slides.
Tomorrows scribe will be Alvina :)
Posted by
Kayla
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4:42 PM
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Today's Slides: March 5
Here they are ...
Posted by
Darren Kuropatwa
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1:01 PM
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Scribe Post for March 2nd
Hello everyone, today was a good day. It was a good day because Mr. K was back in class. I'm glad Mr. K is back and you probably are too.
Today's class was a slack class we did not really learn anything new, all we did was listen to Mr. K clarify what Dr. Eviatar was teaching us in the past week he was away.
He clarified the randBin feature on our graphing calculators. He also clarified The patterns in pascal's triangle.
Sorry the post is so short, there is not really much I can say other than that the class being as slack as it was it felt like a day off of math class.
The next scribe post will be... Jason
Posted by
Eugene
at
12:42 PM
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