Question

Check whether the following Numbers are divisible by 3,9,11 or not a__23597 b__2099705

Answer 1

Answer:

To be divisible by 3 : sum of all digits must be a multiple of 3

To be divisible by 9 : sum of all digits must be a multiple of 9

To be divisible by 11 : The difference of the sum of alternate digits of the                                                      number must be divisible by 11.

a ) 2099705

3 => 2 + 9 + 9 + 7 + 5 = 32

  => not divisible

9 =>2 + 9 + 9 + 7 + 5 = 32

  => not divisible

11 => 23-9 = 14

  => not divisible

b ) 23597

3 => 2 + 3 + 5 + 9 + 7 = 26

  => not divisible

9 => 2 + 3 + 5 + 9 + 7 = 26

   =>not divisible

11 => 14-12 = 2

   => not divisible .

Answer 2

a) 23597

=i) It is not divisible by 3 ,because if we add all the digits we get 26 and it is not divisible by 3

ii) It is not divisible by 9, because if we add all the digits we get 26 and it is not divisible by 9

iii) It is not divisible by 11, because when we add alternate digits i.e. 2+5+7=14 and 3+9=12 and when we subtract 12 from 14 we get 2 and 2is not divisible by

b) 2099705

=i) It is not divisible by 3 ,because if we add all the digits we get 32 and it is not divisible by 3

ii) It is not divisible by 9, because if we add all the digits we get 32 and it is not divisible by 9

iii) It is not divisible by 11, because when we add alternate digits i.e. 2+9+7+5=23 and 0+9+0=9 and when we subtract 9 from 23 we get 14 and 14 is not divisible by 11