12/14/09- Math Notes

What We Did Today-
Convert each fraction to a decimal number. Round each decimal to the indicated place value, then convert to a percent.
A) 27/56 (tenths)

0.4821428

0.5 x100
= 50%

B) 125/396 (thousandths)
0.3156565
0.316 x100
= 31.6%

C) 1496/2005 (hundredths)
0.746134663
0.75 x100
= 75%

Repeating Decimals- A decimal number with a digit or group of digits that repeats forever... Repeating digits are show with a bar example-
Use a calculator to convert these fraction to a repeating decimal-
A) 1/3 = 0.3333333 OR 0.3 with a bar on the top of the three.
B) 5/9 = 0.5555555 OR 0.5 with a bar on the top of the five.
C) 5/6 = 0.8333333 OR 0.83 with a line on top of the 3

Terminating Decimals-
A decimal number in which the digits stop examples include 0.4, 0.86, 0.125

Homework-
Find each of the following as a percent-
a) 23 out of 80
b) 421 out of 560

Change each terminating decimal number to a fraction-
a) 0.48
b) 0.078
Simplify the expression-



Lastly, construct an angle bisector of a 60 degree angle

Remember, it's the dance on Friday, Be sure to finish ALL your work.
+ Be free to ask questions.

math notes

Base

20 E

Height

15 M

find the area and perimeter of all four shapes.

answers

1. 300 m

2. 97.5

3. 97.5

4. 46

sorry if i missed some stuff or my answers are wrong please leave a note and i will try and fix it A.S.A.P

Area of a Triangle

Area of Triangles

Triangle - A three sided figure

- has three angles

eg.

Because a triangle is half of a square, rectangle, or a parallelogram the formula to find a triangle's area is (bxh) divided by 2.

Practise

1. Find the area of triangle ABC

bxh divided by 2 = area of triangle

4x7 divided by 2 = a

28 divided by 2 = a

14 cm squared = area and answer

2.

bxh divided by 2 = area of triangle

4x6.5 divided by 2 = a

13 cm squared = area and answer

3.

bxh divided by 2 = area of triangle

10.5 x 8 divided by 2 = 84

84 divided by 2 = 42

42 mm squared = area and answer

Here is a link that can help you as well.

http://www.mathgoodies.com/lessons/vol1/area_triangle.html

This is a video that can help you.

Angle Bisectors

Angles
-The space between 2 connecting lines

















Acute
-An angle that is less than 90o.













Obtuse
-An angle that is greater than 90o and less than 180o.














Right Angles
-Are angles that are exactly 90o.

Straight Angles
-Are angles that are exactly 180o.













Angle Bisector
-The line that divides an angle into two equal parts.
[Equal angles are marked with the same symbol, O.]





















Method 1 to make an Angle Bisector: Fold paper.






Method 2 to make an Angle Bisector:
Get a compass and make an arc (angle for this step) from the vertex that crosses both arms. Label them X, Y. Then make another arc but from X, Y. They must be the same distance from its point, and have to be intersecting. Now when your done that, draw a dotted line down the X,Y's arc intersection. That is your Angle Bisector. It should look like this.


















Method 3 to make an Angle Bisector:
Grab a protractor. An <>140o. Divide your angle measurement by 2. 140o/2=70o. (There are more steps, but I missed them, and I do not have the proper diagram drawn. I apologize, but i hope you have an idea for what to do next.







HOMEWORK

1. Make a 68o angle. Then draw the angle bisector using two methods.

2. How could you divide an angle into four equal parts?

3. Has each angle been bisected? How do you know?




























Sorry I missed some parts. If I did, be sure to comment on this and tell me.
Hope this was helpful!

Geometry

Parallel - describes lines in the same place that never cross or intersect.
- they are marked using arrows.

Perpendicular - describes lines that intersect at right angles (90degrees)
- they are marked using a small arrow.

measure the distance from: A to B = 8.9 cm B to C = 8.9 cm
E to F = 8.9 cm F to G = 8.9 cm
I to J = 8.9 cm J to K = 8.9 cm

Identify any parallel line segment line:

AE is parallel to BF
BF is parallel to CG
EI is parallel to FJ
FJ is parallel to GK
AI is parallel to CK

Parallel lines are always the same distance apart. No matter where you measure as long as you measure using perpendicular lines.

Now using the same picture ^, identify any perpendicular line segments.
AE is perpendicular to DF
BF is perpendicular to EG
CG is perpendicular to FH

1. Are line segments AE and DF parallel?
2. Are line segments DF and BE perpendicular?
3. Are line segments AC and BG perpendicular?
How do you know?
4. Would a line segment joining A to D be parallel to a line segment BE?
How do you know?

Three Ways To Make Perpendicular Lines

The first way of making bisect perpendicular lines.

1.Draw a line segment on a piece of paper.

2.Make the ends of the line segment point A and point B.

3.Fold the paper so point A is exactly on top of point B.

4.Draw a line down the crease that you have made.

5. Now you can input your right angle in the top right box or the bottom left.

The second way of making bisect perpendicular lines.

1.Using a right triangle draw a line segment on a piece of paper.

2.Still using the right triangle find half of the line segment that you made and make a little mark.

3.Using the right angle of your triangle make another line segment intersecting your original one.

4.Now you can make your ninety degree mark for your right angle.

The third way to make a bisect perpendicular line.

I just found a video to help you with perpendicular lines using a compass.

Just click on this link.

http://www.youtube.com/watch?v=QT28JgIep48

I hope you found my scribe post helpful!

How to draw parallel lines

1. Fold paper
2. Use ruler and a right triangle

How to draw a perpendicular lines

1. Fild paper



2. Use protractor protractor ----------->

How to draw parallel and perpendicular lines

How to draw parallel lines

1. Fold Paper
2. use a ruler

How to draw perpendicular lines

1. Fold paper
2. Use protractor

http://www.aaamath.com/

For homework remember to do page 86-88 number 1-16 and do all numbers.

test

Due to the Remembrance day service we will only have a test on Thursday. Be sure to study each night this week.

Term Test

A reminder that we have a quiz on Tuesday, covering adding, subtracting, multiplying, and dividing decimals. Order of operations will be covered on the test as well.

Lastly, we have a Term Test on Thursday it will cover the entire term's worth of work. Be sure to start studying now, do not wait until the last minute!

November 5th Mathematics

Find the amount each shape weights.

Today's number of the day is :

8497.365

1. Half of the number of the day is : 4248.6825

2. Write the number of the day in expanded form : 8000+400+90+7+0.3+0.06+0.005

3. Write the number of the in written form : Eight thousand four hundred ninty seven and three hundred sixty five thousandths

4. Round the number of the day to the nearest 100 : 8500

5. What digit is in the tenths place : 3

6. The number of the day doubled is : 16994.73

7. 123.45 more than the number is : 8620.815

8. 987.65 less than the number is : 7509.715

10. Cube the digit in the ones place : 343

11. Square the digit in the hundreds place : 16

12. Divide the number by 3.55 and round to the nearest hundreth : 2393.62

13. The product of all the digits in the number of the day is : 181440

For math practice, go to http://www.aaamath.com/grade7.htm

Textbook stuff is homework for the weekend. Do pages 71-73 questions 4-24. Remember to do the even ones only. Due Monday, November 9th 2009.

Number of the Day

Today's number of the day is:2691.348

1. Half of the number of the day is: 1345.674

2. Write the number of the day in expanded form:2000+600+90+1+0.3+0.04+0.008

3.Write the number of the day in written form:Two thousand six hundred ninety one and three hundred forty eight thousandths

4. Round the number of the day to the nearest 100:2700

5. What digit is in the tenths place:3

6. The number of the day doubled is:5382.696

7. 123.45 more than the number of the day is:2814.798

8. 987.65 less than the number of the day is:1703.698

10. Cube the digit in the ones place:1

11. Square the digits in the hundreds place:36

12. Divide the number by3.55 and round to the nearest hundredth:758.13

13. The product of all digits in the number of the day is:10,368



Don't forget to study for the quiz tomorrow!

Home Work

A) 2+3x4=14 B)10-6 ÷ 2=7

2+12= 14 10-3=7

14=14 7=7

C)(2+3)x4=20 D)(10-6) ÷ 2=2
5x4=20 4÷2=2
20=20 2=2

E)8÷22=2 F)4x3÷2+5=11

8÷4=2 6+5=11
2=2 11=11

5x15+33-(156÷2)=6
5x15=75
3x3=9
78-84=6
156÷2=6

Order Of Operations

There are 4 operations:

1st. Brackets

2nd. Exponents

3rd. Divide or Multiply in order from left to right.

4th. Addition or Subtraction in order from left to right.

(6.4+120)x1.25=156.4

What sign goes where? +, /
5.2 / 4 + 2.1= 3.4

1.3+2.1=3.4

Annie has been asked to calculate 1.7+6+2. She claims the answer is 3.85. Do you agree? Explain why or why not.

I don't agree because the answer i got was 9.7. I think she added it wrong. i calculated 1.7+6 and it equaled 7.7 then i added 2 and i got 9.7

Dividing Decimals

Why we estimate

-to get close to the answer.

-is to make the problem easier.

-is to know what to expect from our calculation.



What I estimate and calculate should be close.

1.36 L of O.J. there is for of you.

a) estimate how much you each get.

b) calculate how much you each get.

2.0 divided by 4 would equal 0.5 and that is 1/2 over estimating.

1.0 divided by 4 would equal 0.25 and that is 1/4 under estimating.

1.3 divided by 4 would equal 0.3 (0.36)

1.6 divided by 4 would equal 0.4 (0.46)

or you could use long division
o.34
41.36
-0
______
1.3
-12
______
16
-16
______
0

So then the answer would be that each person would get 0.34 L of O.J.
Here is the next question.
24.6
373.8
-6
______
13
-12
______
18

The answer would be 24.6
Here's a good website you could find more about how to divide decimals http://www.coolmath.com/prealgebra/02-decimals/10-decimals-dividing-by-decimal-01.htm
This is a video on dividing decimals.

This is our home work.
5.4 divided by 0.6
Use number line and estimating and long or short division.

Dividing Decimals

Dividing Decimals

Division means that in the statement 6 divided by 3=2 there are 3 groups of 2 in 6.
Quotient is an answer to a division question.

You have 6 dollars, you need pens for scrapbooking.
Fancy glitter pens cost 0.40 each
How many can you buy?
Use a 100 grid.


15.4 divided by 3.6=427778

15 divided by 3 = 5

4.27778

4.4 divided by 0.42=1047619

5 divided by 0.5 = 10
10.47619

Remember if you use a calculator don't just right the answer down, and remember one dumb finger could change the whole answer!

Remember to do your homework!

20.1 divided by 4.7= 42766
3.5 divided by 0.213= 164319

http://www.math.com/school/subject1/lessons/S1U1L6GL.html

Textbook and Number of the Day

Today's Number Of The Day Is 1279.486

1. Half of the number of the day is: 639.743
2. Write the number of the day in expanded form : 1000+200+70+9+0.4+0.08+0.006
3. Write the number of the day in written form: one thousand two hundred seventy nine and four hundred and eighty six thousandths
4. Round the number of the day to the nearest hundred: 1300
5. What digit is in the tenths place: 4
6. The number of the day doubled is: 2558.972
7. 123.45 more than the number is: 1402.936
8. 987.65 less than the number is: 291.836
10. Cube the digit in the ones place: 729
11. Square the digit in the hundreds place: 49
12. Divide the number 3.55 and round to the nearest hundredth: 360.42
13. The product of all the digits is: 24192



LINK- highlight a word and press the green link button, then look for a site that you think will build interest. then you copy and paste the url. After you get a link click on preview and test the link.










HOMEWORK

textbook is due on Thursday. go on http://www.mytextbook.ca/

Estimating Decimals with Multipilication

1.69 x 5 ( tax included )
Younger sibling says it only costs 5 dollars.
Older sibling says it only costs $10.
What are they thinking , how are they estimating ?
The younger sibling is under estimating. $1 x 5= $5.00 front end estimating
The older sibling is over estimating.$2 x $5= $10 rounded it . Relative size .

Is $9.00 enough, and prove it .
$1 x 5= $5.00 $9 - $5= $4.00 left .
0.69 = 0.70 x 5 = 3.5
$5 + $3.50 = $8.50
OR
$1.69 = $2.00 $2.00 x $5 = $10 0.31 = 0.30 0.30 x 5 = 1.50 $10.00 - $1.50 = $8.50

Where does the decimal go ?
2.2 x 1.8= 3960
2.2 rounded = 2
1.8 rounded = 2 x 2 = 4
4 is the near 3.960.

3.9 x 5.8= 22620
3.9 is rounded to 4
5.8 is rounded to 6 x 4 = 24
24 is close to 22.620

2.57 x 0.45= 1.18220
2.57 is rounded to 3
0.45 is rounded to 0.50 x 3 = 1.5
1.5 is the nearest to 1.18220

A pronghorn is 58 kg .
A Dall's weighs 1.5 times as much
How much does Dall's weigh ?
58 kg = 60 kg x 2= 120 kg
60 kg x 1= 60 kg
90 kg is between 120 and 60.

HOMEWORK
46 x 2.5
64 x 4.5
estimate then calculate

How to scribe

Link-
Highlight a word and press the green button and you look for a site that you think will build interest or get attention. Then you copy and paste the URL. After you get a link copy on preview and test the link.

Image-
Find an Image (Google image) than save it to your computer than browse and find an image that you saved (delete it if you don't want it anymore) you can change the layout and size of image, than you press upload image, than your done.

example:



Video-
Go to YouTube, find a video the will build interest about you topic. Once you find a video, click on it. After go to the grey box and highlight and copy that is in the box, that's titled "embed". Then click edit HTML(on your blog) scroll to the bottom than paste the code , then click compose and preview.






Font-
To change font, click the arrow and go to the word font then scroll down to find a font you like and that other can read.

Colour-
To change the colour the "T" with multi. coloured square and change the colour for important facts or titles. ( Don't use to many colour, else it will be distracting) Try to avoid colours like yellow because it is hard to see. (example: Yellow)

Size-
To change size, click on the double T's, then choose a size of font that you like. (Don't choose a size that's too small or too large)

First Scribepost Room 44

This is our first scribepost.

Check this site out, it is about the best team of all time.

We also have an image to look at.

Try to put a video on.

Mike will create first scribepost. Everyone else will comment!

Good luck have fun.