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Integer Addition : First Principles


    what you'll learn...

overview

In whole numbers, we had studied that addition is combining two quantities represented by the numbers to form a result representing a combined count or measurement.

The integers, both positive and negative integers, are considered and addition is explained for different possibilities.

combine them

In whole numbers, we had studied the following.

Addition - First Principles : Two numbers are considered, each of which represents a count or measurement. The quantities represented by the numbers are combined to form a result representing a combined count or measurement. The combined count or measurement is the result of addition.

eg: 2020 and 1313 are combined together 20+13=3320+13=33.

2020 is an addend

1313 is also an addend

3333 is the sum

Integers are directed whole numbers.

3 is understood as received:3 or aligned to the direction.

-3 is understood as given:3 or opposed to the direction.

receive and give

A girl has a box of candies. The number of candies in the box is not counted. But she keeps track of how many candies she receives or how many she gives away. She maintains a daily account of how many are received or given.

She received 3 candies yesterday. The number of candies received is positive 3.

She gave 3 candies today. The number of candies received today is -3.

She made two transactions, received 3 candies and later received another 2 candies. The numbers in integer forms are received:3=3 and received:2=2.

The total candies received is 3+2=5

receive more, give less

She made two transactions, received 3 candies and given away 2 candies. The numbers in integer forms are received:3=3 and given:2=-2.

The total candies received is, 3+(-2)=1

Considering addition of 3 and -2. The numbers are given in integer form. To understand first principles of addition, let us convert that to directed whole numbers form received:3 and given:2.

The addition is explained as
received:3 is the addend
given:2 is put-in with the addend
=received:1 is the result.

The same in integer form
=3+(-2)
=1

receive less, give more

Considering the box of candies and the daily account of number of candies received or given.

She made two transactions, given 5 candies and then received 2 candies. The numbers in the integer forms are given:5=-5 and received:2=2.

On combining, the total number of candies is, (-5)+2=-3

Considering addition of -5 and 2. The numbers are given in integer form. To understand first principles of addition, let us convert that to directed whole numbers form given:5 and received:2.

The addition is explained as
given:5 is the addend
received:2 is accepted with the addend
=given:3 is the result.

The same in integer form
=(-5)+2
=-3

give and give

Considering the box of candies and the daily account of number of candies received or given.

She gave 4 candies and another time, given away 5 candies. The numbers in integer forms are given:4=-4 and given:5=-5.

On combining, the total number of candies is (-4)+(-5)=-9

Considering addition of -4 and -5. The numbers in the directed whole numbers form are given:4 and given:5.

The addition is explained as
given:4 is the addend
given:5 is put-in with the addend
=given:9 is the result.

The same in integer form
=(-4)+(-5)
=-9

integer addition

The summary of integer addition illustrative examples:

 •  5+3=8
Addition of received: and received: result in received:

 •  3+(-2)=1
received:3 is more than given:2. When received is larger, the addition of received: and given: result in received:

 •  (-5)+3=-2
given:5 is more than received:3; When given is larger, the addition of received: and given: result in given:

 •  (-5)+(-3)=-8
Addition of given: and given: result in given:

The above is concise form to capture the integer addition in first principles.

summary

Integer Addition -- First Principles : Directed whole numbers addition is combining the two amounts with direction information taken into account.

Examples are:
 •  received:3 + received:2 = received:5
3+2=5

 •  received:3 + given:2 = received:1
3+(2)=32=1

 • given:3 & received:2 = given:1
-3+2=-1

 • received:3 & given:5 = given:2
3+(5)=35=2

 • given:3 + given:2 = given:5
3+(2)=5

Outline

The outline of material to learn integers is as follows.

Note: click here for detailed outline of Integers (directed numbers)

    →   Introduction to Directed Numbers

    →   Handling Direction

    →   Ordinal Property

    →   Sign and Absolute Value

    →   Comparing Integers

    →   Predecessor & Successor

    →   Largest & Smallest

    →   Ascending & Descending

    →   Addition: First Principles

    →   Addition: Simplified Procedure

    →   Subtraction: First Principles

    →   Subtraction: Simplified Procedure

    →   Multiplication: First Principles

    →   Multiplication: Simplified Procedure

    →   Division: First Principles

    →   Division: Simplfied Procedure

    →   Numerical Expressions with Integers

    →   PEMA / BOMA