Categories: All - bases - counting - number - operations

by Lauren Bennett 7 years ago

315

MTE 280- Investigating Quantity

In exploring different number systems, the focus is on understanding the various methods of counting and symbolizing numbers used across the world. The Hindu-Arabic system, commonly employed in many countries, operates under a base 10 system.

MTE 280- Investigating Quantity

MTE 280- Investigating Quantity

Integers

Includes how integers are added, subtracted, multiplied, and divided with dependence on their charge (positive or negative).


These operations can easily be shown on a number line to first demonstrate the concept of negative numbers.

Integer: "properties including opposites, positive, negative, number line, and signs"

* Positive Integers are greater than 0

* Negative Integers are less than 0

* Integers are opposite of each other if they have opposite signs and are the same distance from 0 on the number line 



Absolute Value: the value of a number regardless of its sign

* How far a number is away from zero

* Designated by |x| 


Multiplying Positive and Negative Integers 

How I learned to tell what sign the product of two Integers would be: 

https://goo.gl/images/dDeZtT

Whole Number Operations

Number Theory

Number theory includes concepts such as prime numbers and congruence congruence.

Prime Number-

"prime number is a whole number greater than 1, whose only two whole-number factors are 1 and itself."

-Google

Strategies

Strategies

Decomposition

Addition and Subtraction

https://www.google.com/amp/s/www.whatihavelearnedteaching.com/composing-and-decomposing-numbers-for/amp/

Algorithms

Algorithms for Addition/Subtraction

Traditional Method


48 48

+ 33 - 33

_____ _____

81 15


Partial Sums Method


48 1: Add/Subtract the 4 and 3 as they are in their tens place.

+ 33 (Ex. 40+30=70)

_____ Step 2: Add/Subtract the 8 and 3 as they are.

70

+ 11

_____ Step 3: Combine your two sums or find the difference.

81 (Ex. 70+11=81)


Expanded Notation


40 + 8 Step 1: Write each addend in expanded form.

+ 30 + 3 Step 2: Add or subtract by place value.

____________

70 + 11=81



Algorithms for Multiplication

Traditional Method


43

12 x

____

86

430 +

____

516


Partial Products


43

12 x

____

80------> 2x40

6--------> 2x3

40------> 1x4

3--------> 1x3


Models

Addition Problem Types


Subtraction Problem Types


Multiplication Problem Types


Division Problem Types



Properties



Properties of Addition


Properties of Subtraction


Properties of Multiplication



Decimals

When using base 10 block to add, subtract, multiply or divide decimals, flats represent 1 whole, flat are equal to a tenth, units are hundredths.

Method such as 10 block grid papers can also be used for these operations.


Remember: The ones place before the decimal can be seen as a a number of tenths. Ex: 2.0 = 20 tenths

Place Value when working with decimals is slightly shifted to the left when looking at the numbers behind a decimal. The decimal is used as a ones place. For example, the first number after the decimal is in the tens place.


How to Pronounce Decimals:

http://www.themathpage.com/arith/decimals-2.htm


Improper Fractions/Mixed Numbers

Ex: 1 and 1/2


Equivalent Fractions

Ex: 1/2 = 2/4

Fractions

Operations

Adding Fractions


•Area Model

•Numberline Model

•Unit Square


How to use a Unit Square:

https://education.ti.com/~/media/682BA8BCC0FD491298991D9F0189A85C

Subtracting Fractions


•Area Model

•Numberline Model

•Unit Square


How to use a Unit Square:

http://mps.milwaukee.k12.wi.us/MPS-English/CAO/Documents/RtI-Academics/math-intervention-4NF3b_Decomposing_Fractions.pdf

Concepts

Fraction Models

•Area Model

•Set Model

•Linear Model (a row or number line)


*these are used to demonstrate the different concepts involving fractions


Equivalent Fractions- fractions that don't necessarily have the same denominator, but equal the same percentage of their whole

Ex: 1/4=2/8, these can be equivalent because they are the same ratio


Number Systems

Bases

Definitions

Counting Numbers- positive integers, not including fractions or decimals and 0

Digits- counting numbers, single symbols


Types of Number Systems

Different areas of the world may have ways of symbolizing numbers and counting. For example, America, and many other countries use Hindu-Arabic symbols under a base 10 counting system.

Base 12 System

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, x, y

Ex: 1, 2, 3, 4, 5, 6, 7, 8, 9, x, y, 10. . .1x, 1y

Base 10 System

0, 1, 2, 3, 4, 5, 6, 7, 8, 9

Ex: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12

Base 5 System *

0, 1, 2, 3, 4

Ex: 1, 2, 3, 4, 10, 11, 12

Base 2 System

0, 1

Ex: 1, 10, 11, 100, 101, 110, 111, 1000


* "10" is 1 and 0, NOT "ten"


-----------------------------------------------------------------Single, Small Cubes = Ones = Units

Rectangular Block of 10 units = Tens = Long

Square of 10 Longs = Hundreds = Flat

Cube of 10 Flats = Thousands = Cube

Different Systems

Our numerical system is the Hindu Arabic System. Other places and points in time may have other systems such as: