KNOWING OUR NUMBERS

Class - 6th Maths- Chapter -1

-MS.AHSAN ZEHRA RIZVI

INTRODUCTION

● Knowing our numbers helps us in counting objects in large numbers & representing them through numerals.

● Numbers helps in communicating through suitable numbers names & to count concrete objects.

● They help us to say which collection of bigger & arranged them in order.

COMPARING NUMBERS

Numbers are used to show how many there are of something. We’ve been using blocks because it’s easy to see the ones, tens, hundreds and thousands. Normally we’d be using numbers to show how many children, or apples, or teachers, or friends, or whatever we want to show.

Often we want to compare numbers.

For example, if John has 5 apples and Suzy has 8 apples, we might want to know who has more apples.

The Greater Than and Less Than Symbol

We use special symbols to show if a number is greater > or less <

12 < 37 74 > 5812 is less than 37 74 is greater than 58

Memory Aid:

Small side < Large Side Smaller number goes on small side Larger number goes on large side

COMPARING NUMBERS

Comparing Large Numbers

Very often we need to compare large numbers to see which is the greatest or the least. If someone let you pick from two different amounts of money you would probably want the greatest amount!

Rules For Comparing Whole Numbers

● The greater the number of digits, the greater is the number. (unless there are only zeros to the left of the numbers e.g. 007

● If two numbers have the same numbers of digits, the number with the bigger digit on the left hand side is greater.

● If the leftmost digits are the same we compare the next digit to the right and keep doing this until the digits are different.

Important Note: These rules do not necessarily apply when decimals or negative numbers are involved.

PLACE VALUE CHARTINDIAN

Period

Place

Lakhs

Ten Lakhs Lakhs

TL L

Thousand Ones

Ten Thousand

Thousand Hundreds Tens Ones

T Th Th H T O

For example: 9951024 can be placed in place value chart as

TL L T Th Th H T O

9 9 5 1 0 2 4

INTERNATIONAL

Period

Place

Millions

Hundred Millions

Ten Millions

Millions

HM TM M

Thousand Ones

Hundred Thousands

Ten Thousands

Thousands Hundreds Tens Ones

H Th T Th Th H T O

For example: 996743682 can be placed in place value chart as

HM TM M H Th T Th Th H T O

9 9 6 7 4 3 6 8 2

USE OF COMMASIN INDIAN SYSTEM OF NUMERATION

● WE USE ONES, TENS, HUNDREDS, THOUSANDS AND THEN LAKHS AND CRORES.● COMMAS ARE USED TO MARK THOUSANDS,LAKHS AND CRORES.● THE FIRST COMMA COMES AFTER HUNDREDS PLACE AND MARKS THOUSANDS.● THE SECOND COMMA COMES TWO DIGITS LATER. IT COMES AFTER TEN THOUSANDS

PLACE AND MARKS LAKH.● THE THIRD COMMA COMES AFTER ANOTHER TWO DIGITS(SEVEN DIGITS FROM THE

RIGHT).IT COMES AFTER TEN LAKH PLACE AND MARKS CRORE.● FOR EXAMPLE, 5,08,01,592

3,32,40,781 7,27,05,062

ROMAN NUMERALS

● Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers in this system are represented by combinations of letters from the Latin alphabet. Modern usage employs seven symbols, each with a fixed integer value:

Symbol I V X L C D M

Value 1 5 10 50 100 500 1000

● 39 = 30 + 9 = XXX + IX = XXXIX.● 246 = 200 + 40 + 6 = CC + XL + VI = CCXLVI.

FOR EXAMPLES-

QUESTIONS WITH SOLUTIONS RELATED TO TOPICS COVERED-

●

Thank You.