3. Numbers
A Number is a Mathematical object used to count, measure and label.
Example: Natural Numbers (i.e.) 1,2,3,4,5…
Natural Numbers are divided into two types
1. Odd Numbers
2. Even Numbers
4. Odd Numbers
A number is called an odd number if it cannot be grouped equally in twos.
1, 3, 5, 7, …, 73, 75, …, 2009,… are odd numbers.
All odd numbers end with anyone of the digits 1, 3, 5, 7 or 9.
Example: 161, 173, 155, 177, 199
5. Even Numbers
A number is called an even number if it can be grouped equally in twos. 2,
4, 6, 8, ..., 68, 70, . . , 4592,... are even numbers.
All even numbers end with anyone of the digits 0, 2, 4, 6 or 8.
Example: 200, 202, 204, 208
6. Factors
A factor is a number that divides the given number exactly and gives remainder
zero.
Every number has two factors that is 1 and the number itself.
Every factor of a number is less that or equal to that number.
Example : find the factors of 8 and 20
We know that,
8 = 2 X 4;
20 = 2X10; 4X5.
Factors of 8 = 2 and 4
Factors of 20 = 2, 4, 5 and 10
.
7. Multiples
Every multiple of a number is greater than or equal to that number.
Multiples of a number are endless.
Example: Look at the multiplication table of (say) 7:
1 x 7 = 7
2 x 7 = 14
3 x 7 = 21
4 x 7 = 28
5 x 7 = 35 ...
We say that the numbers 7, 14, 21, 28, 35,... are multiples of 7 and they are endless.
8. Assessment Marks: 5 X 1=5
(1) Find out the Odd Number?
A) 26 B) 24 C) 28 D) 29
(2) Find out the Even Number?
A) 31 B) 33 C) 36 D) 39
(3) Find out the Factors of 6?
A) 2, 3, 4 B) 2, 3, 6 C) 2, 4, 6 D) 4, 2, 6
(4) Find out the Multiples of 5?
A) 6, 12, 18, 24 B) 5, 10, 15, 20 C) 7, 14, 21, 28 D) 3, 6, 9, 12
(5) Find out the Multiples of 3?
A) 6, 12, 18, 24 B) 5, 10, 15, 20 C) 7, 14, 21, 28 D) 3, 6, 9, 12
