How to do add, subtract, multiply and divide

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How to do add, subtract, multiply and divide
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Addition
Here 1 ball is added to 1 ball to make 2 balls
Using Numbers it is
 1 1 2
And in words it is
 "One plus one equals two"
The sum of 1 and 1 is 2
Examples
1) 1224
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Subtraction
If you have 5 applesand you subtract 2, you
will be left with 3
This would be written
5 - 2 3
Five minus two equals three
The difference of 5 ?nd 2 is 3
Examples
1) 31 14
Subtraction is defined as adding the opposite
12 15 12 (-15)
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Multiplication
3 groups of 5 make 15
The product of 3 and 5 is 15
5 x 8 40 five times eight equals forty
Examples
1) -4x3-12 minus four multiplied by three
equals minus twelve
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Example there are 12 chocolates, and 3 friends
want to share them, how do they divide the
chocolates?
Using Numbers it is
12 3 4
And in words it is
12 divided by 3 is 4
We use the 12 3 symbol, or sometimes the
symbol to mean divide
Examples
2)
1) 8127
The division is defined as multiplying by
reciprocal
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Slice a pizza, and you will have fractions
Fractions ! A fraction is a part of a whole
3/8
1/4
1/2
Three-Eighths
One-Quarter
One-Half
The top number tells how many slices you have
and the bottom number tells how many slices the
pizza was cut into.
You just have to remember those names! (If you
forget just think "Down"-ominator)
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Numerator / Denominator

We call the top number the Numerator, it is the
number of parts you have. We call the bottom
number the Denominator, it is the number of
parts the whole is divided into.
1)
?all the numerator and denominator of the fraction
3/5
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Equivalent Fractions
Some fractions may look different, but are really
the same


It is usually best to show an answer using the
simplest fraction ( 1/2 in this case ). That is
called Simplifying, or Reducing the Fraction
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Simplifying, or Reducing the Fraction
Another example


1) Reduc? the Fraction 9/12
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Adding Fractions
You can add fractions easily if the bottom number
(the denominator) is the same
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Another example
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Adding Fractions with Different Denominators
But what if the denominators are not the same?
As in this example
1/4
3/8

You must somehow make the denominators the same.
In this case it is easy, because we know that
1/4 is the same as 2/8
2/8
3/8
5/8