Topic 1 (Whole Numbers)-Y4.ppt

8/14/2019 Topic 1 (Whole Numbers)-Y4.ppt

1/23

Murugiah Velayutham/ TCG 1

Teaching of Mathematicsfor Year 4 Primary School

TOPIC 1- WHOLE NUMBERS


2/23


How doyou define Number?

A numberis an idea that represents aquantity. What does a group of four chairsand a group of four people have incommon?

The symbols that we see, write or touchwhen representing numbers are callednumerals.

Hind-Arab numeral: 0, 1,2,.

Roman numeral: I, II, IV,IX..


3/23


Numbers-Definition according toits roles

A number is. Cardinal numbers: How much or how

many. 1, 5, 10,100 etc.

Ordinal numbers: Order, position.1st, 2nd, 3rd.

Nominal numbers: Labels,

identification.651225-08-1234, 016-1234567


4/23


TOPIC 1 WHOLE NUMBERS

INTRODUCTION:Most of the operations in thismodule will cover the content area ofwhole numbers up to 100,000.

We need to teach children(i) to recognize, read and write whole

numbers within the range of 100,000

(ii) to learn on place value and round offwhole numbers within the same range


5/23


1. Reading & Writing Whole Numbers:

(a) Recognising & Reading Whole Numbers- Before the students can read, they

have to recognise the whole numbers

- How could we make them do it???

* Count numbers in groups of ten thousands

Six times a ten thousand is sixtythousands.

Ten times a ten thousand is one hundredthousands


6/23


1. Reading & Writing Whole Numbers:(b) Writing Whole Numbers to 100,000

- How could we make our students writewhole numbers till 100,000???

- Give students the numbers in words- Ask them to read and then write the

number in the table above.......Ninety-nine thousand ninehundred and ninety nine

Thousand Hundred Ten One

Hundred Ten One


7/23


1. Reading & Writing Whole Numbers:(c) Reading Whole Numbers to 100,000

* Add the word and after hundredEg:8,106Eight thousand one hundred andsix.

Eg:67,324Sixty seven thousand three hundred

and twenty four


8/23


2. Place Value:

(a) Knowing Place Value of Numbers to upto 100,000

* Combine all digits in words

* Add the word and after hundred

Eg: 67,324 : Sixty seven thousand three hundred

and twenty four

Thousand Hundred Ten One

Hundred Ten One6 7 3 2 4


9/23


2. Place Value:(a) Comparing Numbers

Algorithm to compare two numbers(i) If Digit Place Value (DPV) for both

data is equal

Bigger number = number with biggerfirst digit

(ii) If Digit Place Value (DPV) for both

data is not equalBigger number = number that hasbigger DPV


10/23


2. Place Value:

(b) Arranging Number:(i) Ascending Order (Count On)

Small value Big value

4 Steps to do listing (Count On)

1. Compare the numbers2. Select the smallest number

3. Place the smallest number on the left

4. Repeat Step 3 until ALL data have been listedin line.

546120 546130 546140 546150


11/23


2. Place Value:

(b) Arranging Number:(ii) Descending Order (Count Back)

Big value Small value

4 Steps to do listing (Count On)

1. Compare the numbers2. Select the biggest number

3. Place the biggest number on the left

4. Repeat Step 3 until ALL data have been listedin line.

546150 546140 546130 546120


12/23


We taught Year 4 pupils to estimatequantities of objects up to 100000.

Students should acquire skills in(i) Estimation: Guess logically

Can you estimatethe number of guests in the

field.I can estimatequite accurately the number of

nut in the packet.

(ii) Approximation: Rounding offBMW 320 is approximately RM 230,000This bungalow is about RM 2 million


13/23


3. Rounding Off Whole Numbers:

- It is useful to round off a wholenumber

- Rounding off whole number is not

exact, it is a round number- When the actual number of objects

is not needed, we can round off

- It is to figure out an estimated

amount of the quantity


14/23



How to Round Off Numbers???Steps to round off a whole number to a specificplace value:

Step 1: Locate the digit in the rounding place.

Look at the right digit

Step 2: Is the digit greater than or lesser than

5? If more than 5, add 1 to the roundingdigit else add 0

Step 3: Replace all zeros to the right digit


15/23



Example:Round 94,762 to nearest thousand

(i) Locate the rounding place that is thousand:

Digit 4. Then look at the digit at the right, 7.(ii) Digit 7 is greater than 5, add 1 to 4

(rounding digit).

(iii) Replace with zeros to the right digit.

The answer is 95,000


16/23


Addition and Subtraction

(i) Understand addition as combiningtwo

groups of objects.

(ii) Understand subtraction as take away

or difference between two groups of

objects.

(iii) Recognize subtraction as the inverseof

addition.


17/23


Addition & Subtraction:-The numbers of place valueare arranged in

the same column.-Add from right to left. Leaving one digit ofthe sum and regroup whatever no more thanone digit to the left column.

th hu ten one th hu ten one1

1 4 9 7 1 3 1 4 9 7

+ 1 4 2 2 2 - 1 4 2 22 9 1 9 3 3 0 0 7 5


18/23


Multiplication & division

Multiplication as RepeatedAddition. Multiplication operation as an array

or rectangular display.

Division- Sharing equally

Division -Repeated subtraction


19/23


Multiplication Algorithm

Algorithm 1 Algorithm 2 Algorithm 3

1 6 4 1 6 4 1 6 4

x 6 x 6 x 6

9 8 4 2 4 2 4

3 6 3 6 0

6 6 0 09 8 4 9 8 4


20/23


Division Algorithm

Algorithm 1 Algorithm 23

3 01 3 3 1 0 0

7 9 3 5 7 9 3 57 7 0 02 3 2 3 52 1 2 1 0

2 5 2 52 1 2 1

4 4

M lti li ti & Di i i i


21/23


Multiplication & Division inEveryday Life

Example 1:There are 25 packets of sweets andin each packet there are 142 sweets.

How many sweets are therealtogether?

1 4 2

x 2 5

M lti li ti & Di i i i


22/23


Multiplication & Division inEveryday Life

Example 2:3550 sweets are to be divided into 25packets. How many sweets are there ineach packets?

1 4 2

25 3 5 5 0- 2 5

1 0 5- 1 0 0

5 0- 5 0

0


23/23

Topic 1 (Whole Numbers)-Y4.ppt

Documents

Transcript of Topic 1 (Whole Numbers)-Y4.ppt