Operations

An operation is a rule , or set of rules, for processing one or more object.

A binary operation is one which combines two objects to make a third.
Addition, Subtraction, Multiplication and Division are all examples.

An operator is the symbol used to show which operation is to be done.

               

+ Addition

Augend : the number to which another is added.
Addend : the numbers to be added together.
Summand : a quantity to be added to another.
Sum : the result of addition of numbers

augend + addend = sum

- Subtraction

Minuend : the amount from which something is to be subtracted..
Subtrahend : the number to be taken away
Difference: the result of subtraction of numbers.

 minuend − subtrahend = difference

x Multiplication

Multiplicand : the amount which is to be multiplied.
Multiplier : the amount by which to multiply.
Product : the result of a multiplication.

 multiplicand × multiplier = product

÷ or / Division

Dividend : the amount which is to be divided
Divisor : the amount by which to divide.
Quotient : the whole number result of dividing numbers
Remainder : what is left over, often expressed as a fraction of the divisor.

dividend ÷ divisor = quotient + (remainder ÷divisor )

  The division algorithm


A commutative operation is one in which the order does not matter.
The numbers can move around.

2

Addition is commutative  since   3 + 2 = 2 + 3 

Subtraction is not, since 3-2 ≠ 2-3

Multiplication is commutative  since   3 x 2 = 2 x 3 

Division is not, since 3÷2 ≠ 2÷3

 7 +( 5 +2 ) = 7 + ( 2+5)  = 14


12

A binary operation is associative if  grouping  makes no difference.
The numbers can freely associate with each other!

Addition is associative  since   3 + 2 +5 = 3 + ( 2 + 5) 

4 + (5 +6) = (4 + 5) + 6 
Subtraction is not, since 5-3-2 ≠ 5-( 3 - 2)
 Multiplication is associative  since   3 x 2 x 5 = 2 x (3 x 5)   

Division is not, since 12÷ 3÷2 ≠12÷(3÷2)


The distributive property of  multiplication over addition or subtraction.

Multiplying a sum by a number gives the same result as multiplying each addend by the number and adding the result.

1

In general,

2

Usually, the multiplication sign is left out.

3

Removing brackets


The identity for a binary operation on a set is an object in the set which is combined with an operator on  any second object to produce a result equal to that second object.

12

 

e.g.    a + 0 = a = 0 + a            
so 0 is the identity for addition.

Addition

12

Multiplication

12

Subtraction

12

Division

12

 

Number Bases

1

2

 

Examples

1510  =  11112=  305

(This is read as 15 in base ten is equal to 1111 in base 2 or thirty in base 5)

4 5 55

The subscript shows the base.

They can also be written 15dec = 1111bin  
where dec stands for decimal and bin stands for binary

In Hexadecimal, the letters  A to F are used to represent
the numbers from 10  to 15

A =10  B = 11  C = 12     D = 13     E=14     F=15

So  1220 dec = 4C4hex

6 7

 

 

Converting bases