Children's House of 
-Math
Growing Old is Mandatory.... But ... Growing up is Optional!
If You Are 9-12 years old; and You Love MATH ... This Page is for you! You will have fun. While you learn with me the most amazing FUN Shortcuts OF MATH.
Signs, Definition, Adding, Multiplying & Dividing numbers with signs
Definition:
- A sign in front a number will indicate if it is positive or negative value
- Below, you will value some (not all) examples of where a Positive or a negative values mean or could be used:
- Increase or decrease in value; like gaining weight. If I gain 5 pounds, this could be expressed as +5 pounds. If I loose weight, this could be expressed as -5 pounds
- Above or below the zero level (Temperature): all numbers above the zero are expressed with a positive sign, like +23 degrees (this means 23 degrees above zero), - 45 degrees (this means 45 degrees below zero), and so on, and so on.
- Adding or taking away something: if I add 5 dollars to my money, this could be expressed as +5. If I take 5 dollars from my money, this could be expressed as -5
- Going forward and backward: If I go forward 6 steps this could be expressed as +6. If I go backward 7 steps, this could be expressed as -7 ( the same applies for going up and down)
Adding
Adding two numbers with the same sign
Add the numbers and put the common sign
Examples
Add +4 & +7 :
Common sign is +
Add the numbers: 4+7=11
Answer is +11
Add -5 & -6
Common sign is -
Add the numbers: 5+6=11
Answer is -11
Adding two numbers with the different signs
:
Subtract the small from the big and put the sign of the bigger one
Examples
Add +4 & -7 :
Sign of the bigger is -
Subtract 4 from 7 = 3
answer is -3
Add -5 & +6
Sign of the bigger is +
Subtract 5 from 6=1
Answer is +1
Homework
Add the following numbers:
- +5 & +18
- +6 & +7
- +7 & - 18
- +67 & +123
- - 45 & -34
- -23 & +24
- -267 & +234
- -28 & +456
- -123 & -2
- +23 & -23
For the answers of your Homework Click
Here
Multiplication or Division
(Same rules apply for multiplication and division)
carry the multiplication or the division as if the signs do not exist
If the signs are the same, the answer will have a + sign
If the signs are different, the answer will have a - sign
Examples:
- Multiply + 5 by +6
- Signs are the same, the answer will have +
- 5x6=30
- The answer is +30
- Multiply - 5 by +4
- Signs are different, the answer will have -
- 5x4=20
- The answer is -20
- Multiply - 5 by -6
- Signs are the same, the answer will have +
- 5x6=30
- The answer is +30
- Divide + 15 by +5
- Signs are the same, the answer will have +
- 15/5=3
- The answer is +3
- Divide -30 by +6
- Signs are different, the answer will have -
- 30/6=5
- The answer is +5
- Divide -30 by -6
- Signs are the same, the answer will have +
- 30/6=5
- The answer is +5
Homework (B)
Multiply the following Numbers:
- +34 X +2
- +12 X +2
- +5 X +4
- -5 X - 4
- -13 X +3
- - 23 X -2
- -3 X + 11
- -11 X - 11
- -200 X + 2
- - 23 X +2
For the answers of your Homework Click
Here
Other Cool-Math Topics
-
Multiplication of any 2 digits number by 11
- Helping Your Child at Home to explore Numbers & Fractions
- Multiplication of any 3,4,5, ....etc digits number by 11
- Vertical Multiplication
- Verify your Multiplication's
- Multiplying any Number (one digit) by 9
- Multiplying any 2 digits number that ends with 5 by itself
- Can a number be divided by 2, 3, 4, 5, 9 or 10
- Units Conversion
- Definition & Understanding of Decimal
- Multiplication and division of a decimal by 10,100, 1000, .....etc
- Multiplication of decimal numbers by each others
- Division of decimal numbers by each others
- Signs, Definition, Adding, Multiplying & Dividing numbers with signs
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Children's House of -Math
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If you have comments or suggestions, or you want to write to my son. E-mail me at
smedleg@securenet.net
I will see you tomorrow with another shortcut ... Have a nice evening. And do not forget to do your Homework!
Yahooligans!
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