Divisibility Test - Practice Test

Answer : C

Explanation:If a number is divisible by 9, the sum of its digits must be a multiple of 9.     Here, 2+7+4+5+2=20, the next multiple of 9 is 27.       7 must be added to 27452 to make it divisible by 9.

If a number is divisible by 6 , it must be divisible by both 2 and 3
In 522x, To this number be divisible by 2, the value of x must be even . So it can  be 2,4 or 6 from given options
552x is divisible by 3, If sum of its digits is  a multiple of 3  .
5+5+2+x =12+x  ,  
If put x =2 , 12+2=14 not a multiple of 3
If put x =4 , 12+6=18  is a multiple of 3
If put x =6 , 12+2=14 not a multiple of 3
The value of x is 6.

A number is divisible by 11 when the difference between the sum of digits at even places and at odd places is 0 or multiple of 11

The given number is 7648x.  

(Sum of digits at EVEN places) – (sum of digits at ODD places) = 0

⇒ (6 + 8 ) - ( X + 7 + 4 ) = 0

⇒ 14 - ( X + 11 ) = 0   

Here the value of x must be 3
So, the least value of x is 3.

Answer : C

Explanation:In aptitude tests , we get questions on divisibility by 11.A number is divisible by 11, when the difference between the sum of digits at even places and at odd places is 0 or multiple of 11The given number is M183.    (Sum of digits at EVEN places) – (sum of digits at ODD places)=0                        (8 + M )- (3+1)= 0                        (8 + M ) -  4  =  0            Here the value of M must be 7 .

Answer : C

Explanation:If a number is divisible by 9, the sum of its digits must be a multiple of 9.     Here, 5+3+2+8+6+9=33, the next multiple of 9 is 36.3 must be added to 532869 to make it divisible by 9.