## Monday, October 31, 2011

### Dividing Rational Number in Fraction Form

Step 1
-Change Mixed fractions to improper fractions
Step 2
-Make the problem simpler by dividing by 1
-Multiply the divisor by its reciprocal and the dividend by the same reciprocal
Step 3
-Simplify if possible

Here is a link to :
Dividing Rational Number in Fraction Form

Homework:
-Journal
-Finish 2.3 and Yellow decimal sheets
-Start Fraction yellow sheet

## Thursday, October 27, 2011

Add and Subtract Rational Numbers in Fraction Form
Step 1   Find a common denominator
Step 2   Use the sign rules to
Step 4   Simplify if possible

Example:

To Subtract a Fraction
Step 1   Find a common denominator
Step 2   Find the equivalent fraction
Step 3   Use the sign rules to
Step 4   Subtract the numerator
Step 5    Simplify if possible

Example

To Multiply
Step 1   Change mixed number to improper fraction
Step 2   Multiply the numerator with the numerator and multiply the denominator with the denominator
Step 3   Use the sign rule
Step 4   Simplify if possible

Example:

Homework!
Everything in 2.3

## Wednesday, October 26, 2011

### Derec's Math Post

1. Put the numbers in a vertical column, aligning the decimal point.
2. Add each column of digits, starting on the right and working and working left . If the sum of a column is more than ten, "carry" digits to the next column on the left.
3. Place the decimal point in the answer directly below the decimal points in the terms.n

(+) + (+) = +
(-) + (+) = -
(+) + (-) = Absolute Value
(-) + (+) = which ever is greater, keep the sign

Subtracting Decimal .
1. Put the numbers in a vertical column, aligning the decimal points.
2. Subtract each column, starting on the right and working left. If the digit being subtracted in a column is larger than the digit above it, "borrow" a digit from the next column to the left.
3. Place the decimal point in the answer directly below the decimal points in the terms.
4. Check your answer by adding the result to the number subtracted. The sum should equal the first number.

(+) - (-) = +
(-) - (+) = -
(+) -(+) = Absolute Value
(-) - (-) = Absolute value

For example.

89.9 + 43.3 = 133.2
1 1
89.9
+ 43.3
_______
133 .2

46.65 - 16.2 = 30.45

46.65
- 16.20
________
30.45

Multiplying and Dividing Decimal

Here are the rules for multiplying decimal numbers:

1. Multiply the numbers just as if they were whole numbers:
*Line up the numbers on the right--do not align the decimal points.
*Starting on the right, multiply each digit in the top number by each digit in the bottom number, just as with whole numbers.
2.Place the decimal point in the answer by starting at the right and moving the point the number of places equal to the sum of the decimal places in both numbers multiplied.

(-) x (+) = -
(+) x (-) = -
(+) x (+) = +
(-) x (-) = +

for example

37.7 x 2.8 =

37.7 ( 1 decimal place )
x 2.8 ( 1 decimal place )
________
3016
+ 754
________
105.56 ( 2 decimal places, move point 2 places left )

To divide decimal numbers:

1. If the divisor is not a whole number, move decimal point to right to make it a whole number and move decimal point in dividend the same number of places.
2. Divide as usual. Keep dividing until the answer terminates or repeats.
3. Put decimal point directly above decimal point in the dividend.

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

for example:

16.9 ÷ 6.5 = 2.6

2.6
____
6.5 /169.0
- 130
__________
390
- 390
__________
0

To check our answer, we multiply the quotient by the divisor and make sure it equals the dividend:

2.6
x 6.5
______
130
+ 156
______
16.90

Homework!
-Finish all worksheets
-Homework Book
-Math Textbook;leftover work

## Monday, October 24, 2011

### Ryan's Math Post

Minuend-Subtrahend=Difference
Factor+Factor=Product
Dividend/Divisor=Quotient

10x1000=10 000 0.1x1000=100
10x100=1 000 0.1x100=10
10x10=100 0.1x10=1
10x1=10 0.1x1=0.1
10x0.1=1 0.1x0.1=0.01
10x0.01=0.1 0.1x0.01=0.001
10x0.001=0.01 0.1x0.001=0.0001
10x0.0001=0.001 0.1x0.0001=0.00001

A good way to multiply hard decimals is:
121 1.21
x13 x1.3
----- ------
363 1.573
1210
-------
1573

A rule for multiplying decimals could be: Add how many decimal places are in each factor to get the decimal place value in the product.

Examples:
1 + 1 = 2
0.2x0.2=0.04
3 + 3 = 6
0.111x0.1111=0.012321
4 + 4 = 8
0.1111x0.1111=0000.01234321

100/10=10 0.001/0.1=0.01
10/10=1 0.01/0.1=0.1
1/10=0.1 0.1/0.1=1
0.1/10=0.01 1/0.1=10
0.01/10=0.001 10/0.1=100
0.001/10=0.0001 100/0.1=1 000

A rule for dividing decimals could be: Subtract how many decimal places are in the dividend and divisor to get the decimal place value in the quotient.

Examples:
2 - 1 = 1
0.02/0.4=0.5
2 - 3 = -1
0.02/0.006=3.33..

Homework!

-Finish all 2.2 worksheets
-Homework Book
-Math Textbook;leftover work

## Sunday, October 23, 2011

### ADD AND SUBTRACT RATIONAL NUMBER IN DECIMAL FORM

EXAMPLE:

+25.14
-13.07
=12.o6

first estimate 25.14 and 13.07 equal +25
-13
=12

remember -25 is absolute value

## Saturday, October 22, 2011

### The Rules of finding the decimal/fraction between decimals

Rules

1) Imagine as many zeros as you want after the least place value after decimal.

2)Put a digit in the next place value.

3) Change decimal into a fraction...... simplify if possible.

Example:

Find the fraction between
0.452 and 0.453
\ /
45,230 22615
------- = ------
10,000 50000

## Tuesday, October 18, 2011

### Finding Fractions

How to find a fraction between two given numbers:

One way:

1. Convert one or both numbers to a fraction
2. Find a common denominator
3. Find a numerator between the two numerators of the step 2 fractions

Example:

Another way:

1. Convert one or both numbers to a decimal
2. Find a decimal number between the two numbers
3. Convert to fraction
4. Find fraction in lowest terms if possible

Example:

Homework:

Finish 2.1 in homework book and re-read the pages if you don't understand something.
Go on this website and get your bronze badge in 6 days

## Saturday, October 15, 2011

### Rational Numbers and Reciprocals

In class, we learned about different ways of finding the value of x when dealing with rationals.
There are three ways:

WAY #1:

WAY #2:
WAY #3:

We were asked to find a way to make the following fractions equal:

To do this, you must use cross multiplication.

This means that when you cross multiply, you simply multiply the two numbers that are opposite from each other.

So for the example below, you would multiply 3 and 8, and 6 and 4. This would get you 24 for both.

* A reciprocal is when you multiply a rational to equal 1.
Some examples are:

KRISTEL WILL BE DOING THE NEXT BLOG POST!

## Thursday, October 13, 2011

### Comparing and Ordering Rational Numbers

Quiz
Change 0.13repeating into a fraction: 2/15
What is between 1/5 and 2/3? 0.
What is -0.4 as a fraction (in lowest terms): -2/5

*If there is a odd number of negative signs, the answer is a negative*

*If there are a even amount of negative signs, the answer is positive*

HOMEWORK:
Check Your Understanding #1-3 pg. 51-54
Practise: 4 or 5, 6 or 7, 8 or 9, 10 or 11, 11 or 12, 12 or 13, 14 or 15, 16 or 17
Apply Odd or Even
Extend 28, 29, 30
ALSO! DON'T FORGET TO BE STARTED ON YOUR BIRDHOUSE, IT IS DUE ON MONDAY!

MELANIE ILAGAN IS DOING THE NEXT BLOG POST.

## Tuesday, October 11, 2011

### Ivan's blog post

Project:
Build a birdhouse.

- Base 10x10cm

- Sides 20cm

- Middle 26cm

- Roof hangover 3cm

- Hole 2.5 cm in diameter

- Under cylinder pearch arm 4cm L, 1cm D

- Roof tiled 25cm*30cm tiles

- Make a net of the birdhouse!

- Find number of tiles needed

- Creat a design showing line of symmerty.

- Other side design showing rotational symmerty.

DUE MONDAY! + ALL journals, and POW.

Homework: - Journal writing. (What you learned about todays work.)

- Find rational numbers & understand what they mean.

DOMENICO WILL BE DOING NEXT BLOG.

## Tuesday, October 4, 2011

### AJ's Blog Post

Today in math class, we learned how to convert centimetres into metres.
You need to multiply the number by 10 000 to get from centimetres in to metres

### Brandon's Math Post

Today in class we reviewed on how to find a cylinder with a piece in the middle.

How to find the TSA of this object

TSA
= Large cylinder - small circles + cylinder
= 2πr^2 + 2πrh - 2πr^2 + 2
πrh
= 2π4^2 + 2π4(20 - 2π3^2 + 2π3(20)
= 2
π16 + 2π80 - 2π9 + 2π60
= 32
π + 160π - 18π + 120 π
= 294
πm^2

The height of this triangular prism is 8m, the base is 6m and the length it 10m
Tile it with 10x20cm tiles. How many tiles are there?
So what I did is:

a^2+b^2 =c^2
8^2+3^2 = c^2
64+9 = c^2
73 =c

square root 73 = square root c^2

8.54 = c

SA roof = lw
= (8.54x10)
= (85.4)
= 170.8m^2

Tile = 10 . 20
= 200cm^2

lm^2 = 100cm x 100cm
= (100 cm)^2
= 10 000 cm^2

170.8 x 10 000

1708000 cm^2 / 200 cm^2 = 8540

I will need 8540 tiles.

The third and final figure.

Tiles are 15 x 30 cm, how many tiles are there?

a^2 + b^2 = c^2
4^2 + 2.5 = c^2
16 + 2.5 = c^2
22.25 = c^2
square root 22.25 = square root c^2
4.72=c

SA roof = l w
= 4.75 x 8
= 37.76
= 75.52 cm^2

S.A = 9x(s^2) 8(4^2)
= # (face(s^2) 8(16)
= 9(3^2) 128 cm^2
= 9(9)
=81 cm^2

S.A = top + 4 sides
= s^2 + 4 (lxw)
= 2^2+ 4(2) (3)
= 4+4(10)
= 44 cm^2

HOMEWORK
Workbook + textbook + Vocabulary + Test review,
Practice sheets

Ivan will be doing the next blog.

P.S. Sorry for the small pictures.