3rd Class Mathematics Numbers

Numbers

• The number system contains ten digits 0,1,2,3,4,5,6,7,8,9.

Largest and smallest numbers:

• The smallest one digit number is 1.
• The largest one digit number is 9.

• The smallest two digit number is 10.
• The largest two digit number is 99.
• The smallest three digit number is 100.
• The largest three digit number is 999.
  • 10 Ones = 1 Ten
  • 10 Tens = 1 Hundred
• 10 Hundreds = 1 Thousand

Place Value of each digit in a number:

In a four digit number, there are four places named:

Ones place. Tens place. Hundreds place and Thousands place.

Ex:  

Ascending Order of numbers:

Arranging numbers from the least number to the largest number is called Ascending Order.

Ex: 13, 67, 132, 168 are in ascending order

Descending Order of numbers:

Arranging numbers from the largest number to the least number is called Descending Order.

Ex: 168, 132, 67, 13 are in descending order.

Symbols used for comparison of two numbers:

This is the "equal to” sign. When we use it between two numbers, it means that the numbers on both sides of the sign have the same value.

Ex: 53 = 53

This is the "greater than" sign. It is placed between two numbers in such a way that the

open side is towards the bigger number.

Ex: 43 > 34

This is the “less than" sign. It is placed between two numbers in such a way that the closed side is towards the smaller number.

Ex: 57 < 69

Rules for comparison of numbers:

Rule 1:

A numeral containing more digits is greater.

Ex: 163 > 35

Rule 2:

If two numerals contain the same number of digits, the numeral having greater digit at the left most place will be greater.

Rule 3:

If the left most digits are also the same, we go to next digit from left and compare.

Successor of a numeral:

Successor of a particular numeral comes just after that numeral. So, we can find out the successor of a numeral by adding 1 to the given numeral.

Ex : The successor of 99 is 99 + 1 or 100.

Predecessor of a numeral:

Predecessor of a particular numeral comes just before that numeral. So, we can find out the

predecessor of a numeral by subtracting 1 from the number.

Ex : The predecessor of 100 is 100 - 1 or 99.

Even numbers:

The numbers that have 2, 4, 6, 8 and 0 in the ones place are called even numbers.

Ex: 4,32, 168, 490

Odd numbers:

The numbers that have 1, 3, 5, 7 and 9 in the ones place are called odd numbers.