Scribe Post for February 8, 2010

Today, we went over our ratio worksheet that was given to us last friday during the test. Mr B went over how to do the worksheet.

Here is an example:
the scale of a map is 2in= ___mi
map: 5in
actualy: 32.5mi

This is the first method you could use in finding the answer:

Here is another way in solving this question:
So you see, either way you solve it, you still get the same answers.
After that, we just worked on the other sheets he gave to us.

MATH HOMEWORK
1. Math Journal
2. Check that blog Mr. B showed us
3. Look at the videos and stuff thats on the grade nine homepage
4. Stash it
- All Math Links including Intro and Wrap it up
- One of your tests signed
-Math Journal
- Self Assessment
- Chapter 4 Blog Problems

THANK YOU FOR LOOKING AT MY POST :) I'm sorry if I took a long time to make this post, but I hope you like it! :) And also, I'm not sure how to make the picture bigger so I'm sorry if its too small. ANYWAYS, the next scribe is... dun dun dun...... DEAN (: (:

The Spiral Rational Game

The Spiral Rational Board Game Rules.

RED SPACES - Go back on space
BLUE SPACES - Pick up a card

GREEN SPACES - Go forward one space

Cards
- When you land on a blue space, someone (it could be anyone of the players) picks up a card and reads it to you, then you have to answer. If you got it wrong, you miss a turn, and if you got it correct, you are safe until your next turn.

How to start
- To start a game, you have to choose which colour cone you want to be. (UP TO 4 PLAYERS). To choose who goes first, each person gets to roll the die, whoever gets the highest gets to go first and the second person is the person who got the second highest and so on. The winner is the person who has reached to the finish line before everyone else.

Hello Mr. Backe (:

HI HI HI HI (: (: MERRY CHRISTMAS MR. BACKE! and a happy new year (: We all know that you have been away for quite a while, and we missed you very much and we hope you are doing well. Thank you for being such a great teacher. For teaching us how to do math so that we can become brilliant students at different schools in the future. Thank you so much for being so kind to us and giving us chocolate (: Thank you for spending your lunch breaks, mornings and after school just to help us if we needed anything. We are all very grateful to have you as a teacher! (: We "THE CLASS" wish you a merry merry christmas (:

Scribe Post for December 1, 2009

Question 11

Hello there my fellow classmates. (: Today, I will be showing you how to answer question 11.

In every day speech, in a jiffy means in a very short time. In science, a specific value sometimes assigned to a jiffy is 1/100 s. Naima can type at 50 words/min. On average, how many jiffies does she take to type each word?

The first step is to find out how many jiffies does she take to type each word, you have to multiply 1/100 by 60 seconds because you need to find out how many jiffies are in a minute.

In one second, there are 100 jiffies, and in 60 seconds, there are 6000 jiffies. To find out how many how many jiffies does she get to type each word you divide it by 50 because each minute she can type fifty words.

So, now all you have to do is add a sentence because it is a word problem.

She takes 120 jiffies to type each word.

So, to be honest, I didn't know where to start with this question. It took me awhile to figure out how I got the answer and how to explain it for you guys to understand it better. I hope my explanations are well enough for you to understand and not to confuse you more about this question. Well, I hope you enjoy my post and don't forget to COMMENT! (: Tootles!

Question #14

Hey, 9-05! Today I will be showing you how to solve the question 14 on page 6o.

14. Saida owned 125 shares of an oil company. One day, the value of each share dropped by $0.31. The next day the value of each share rose by $0.18. What was the total change in the value of Saida's shares?

The bolded coloured words are the important words that we need to know in order to solve this question. So, since there are 125 shares, and EACH share dropped by $0.31, we multiply 125 to 0.31.

Then, using the 125 shares again you multiply 125 to 0.18 because you have to figure out how much rose in one day with 125 shares.
Let's see what we have so far:
-38.75 is how much dropped.
- 22.5 is how much rose.

Now, what we have to do is we have to subtract how much dropped to how much rosee so we could find out the total change of value of Saida's shares.
The last step is, (Well, its actually the first step, but I'm just putting it up last) writing a simple sentence because it is a word problem.

The total change in the value of Saida's shares is 16.25.

This is the end of my post, I hope you enjoyed looking at it and hopefully, you learned alittle more from it. Feel free to comment if I did anything wrong and thanks for reading! (:

Scribe Post for October 26, 2009

Hello there 9-05! (: First things first, I would like to say HAPPY BIRTHDAY JOSEPH! Anyways, the first thing we did in class today was we went over questions that we did not understand.

One of the questions that was asked was, how can you put -1 1/2 into an improper fraction when there is a negative integer?

Well, as you can see, I put the negative signs red. The reason why I did that is because first, we solve the question without the signs then we add it on afterwards. The first thing we do is we add the whole number (1) to the denominator (2) and that equals to 2. Then, we add the 2 to the numerator (2) which equals to three. Since we are making this into a proper fraction, we add the denominator. Which the answer equals to 3/2. Now that we have solved everything, all we have to do is add the negative signs.

After that, Mr. B asked us to change 0.16 (16 is repeating) into a fraction. The answer we got was 16/99. Do you know why? Here, I will show you.

Do you get it? Well, to find the fraction of it you have to times it by 100x. We do that because a fraction is out of a hundred, and the "x" stands for the number we are trying to find. The reason why we use the number 16.16 is because we have to move units down because of the 100.
(I'm sorry if you dont understand, I'm bad at explaining.. but I will try my best to help you)Then 100x-x = 99x. You get the the answer 99 because when you have 100 bananas for example and you take one away there are 99 bananas. The "x" does not change anything, the "x" represents as 1. Then the 99's cancel eachother out and then it becomes x=16/99. If you want to make sure it is correct, you can check it with a calculator to see if the answer is really 0.16 repeating.

Here are other examples of what we did in class:
0.23 (repeating on 23)

0.16 (repeating on only the 6)

You are probably wondering how to do this right?

Some of the possible answers are: 16.5/99, 6/9. 1/6. 16/9.
Which one is the correct answer?

Let's see. 0.016 (16 is repeating)
What is the answer?

16/990 or 16/999?

Homework:

Find the Fractional Expression for these numbers.
0.2 (repeating on the 2)

0.43 (repeating on 43)

0.172 (repeating on 72)

How to find the answer to:

3/5 - 3/8=?

AND

of course Math Journal .

AND... just because we are "THE CLASS", here is a video if you are still having trouble (:

oops. nevermind. I can't seem to find anything... because when I looked for a video, it says instead of 100x, its 10x.. I don't really understand why.. but I will ask Mr. B tomorrow (:

Well, I hope you guys enjoyed reading my post.. I am sincerely sorry for not posting the part about the chess problem. I don't understand it and plus, I have to study for french. So, I'm very very sorry. I appreciate your time looking at my work and comment if you'd like (: OH! I almost forgot, the next scribe is...... ABBY ! (:

Rational Numbers

For some of you that didn't know yet, our next unit is on rational numbers. First of all, what is rational numbers?

Rational Numbers:
- A number that can be expressed as the quotient of two integers, where the divisor is not zero. Which means that a number that can be put into a simple fraction.

For example:
-half in decimal form is 0.50 and when it is written in a fract it is 1/2.

Irrational Numbers:
- The opposite of rational numbers. The number cannot be expressed as the quotient of two integers, where the divisor is not zero. Which means that you can't put a number into a simple fraction.

For example:
-a number that goes on and on and on and never stops, 0.12345678910111213141516...


I hope you like my post! (:

Elegant Algebraic Expressions

Hello everyone! I am making this blog post to show you the most elegant algebraic expressions for the surface area of a cube, rectangular prism, and a cylinder. I will also be answering some questions.

SURFACE AREA OF A CUBE = 6s²



S.A. = 6s²
S.A. = 6(2²)
S.A. = 6(2x2)
S.A. = 6(4)
S.A. = 24u²


SURFACE AREA OF A RECTANGLE = 2(lw)+2(lh)+2(hw)

S.A. = 2(lw)+2(lh)+2(hw)
S.A. = 2(5x6)+2(5x4)+2(6x4)
S.A. = 2(30)+2(20)+2(24)
S.A. = 60+40+48
S.A. = 148cm²

SURFACE AREA OF A CYLINDER = 2πr²+2πrh

S.A. = 2πr²+2πrh
S.A. = 2π(4²)+2π(4)h
S.A. = 2π(4x4)+2π(4)h
S.A. = 2π(16)+2π(4)
S.A. = 32π+8π
S.A. = 100.48+25.12
S.A. = 125.6cm²

COMPOSITE SHAPES
- a composite shape is a shape that can be divided into basic shapes, like a square, a rectangle, a triangle, etc.

This figure can be divided into two basic shapes, a triangle and a square.

HOW DOES SYMMETRY HELP US SOLVE SOME OF THESE SURFACE AREA PROBLEMS?
It helps us solve some of these area problems because some of the shapes have symmetry. Some shapes have sides that are the same, like, a square. all 6 sides have identical sides. If we know that there it has identical sides, then we can form a formula to solve the surface area of the shape.

WHAT HAPPENS IF A PART OF ANY OF THESE SHAPES IS MISSING? HOW DO I FIND SURFACE AREA THEN?
If there was a part missing in any of these shapes, you would have to calculate the missing area, and subtract it from the original shape.

THANK YOU FOR READING MY BLOG POST ! (: I hope this helps you learn more about surface area and please feel free to comment if I made any mistakes.

Why 360?

Do you know why 360 degrees is a full circle? The reason why we use the number 360 is because it started with the Babylonians.





Now in the present, we use the base of 10, when once in the past, the Babylonians used the base of 60. That system that they used was called the Sexogonal System. The Babylonian also made a calendar that had 360 days because they believed that the earth has a full rotation after every 360 days.







Also, if you haven't noticed, 360 is a very handy number. It can be divided by alot of numbers. It has alot of factors such as: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180, 360.

I hope you guys learnt something number about why we use the number 360. Please comment if you would like to add something to my post (: