Question

check whether the given numbers are divisible by '11' or not? a)786764 b)536393 c)110011 d)1210121 e)758043 f)8338472 g)54678 h)13431 i)423423 j)168861​

Answer 1

Given: the numbers:  a)786764 b)536393 c)110011 d)1210121 e)758043 f)8338472 g)54678 h)13431 i)423423 j)168861​

To find:  whether these numbers are divisible by 11 or not.

Solution:

As we know that the divisibility test for 11 is:

• Divisibility rule for 11: If in any number, the sum of the numbers in the even positions = sum of the odd numbers in the odd positions, then the number is divisible by 11.
• Also, the difference of the sum of the numbers in even positions and the sum of the numbers in the odd positions = 11.
• So now, checking all the numbers for this test:

• a) 786764 = 7+6+6= 8+7+4

• So this number is divisible by 11.

• b)536393 = 5+6+9 ≠ 3+3+3
• So this number is divisible by 11.

• c)110011 = 1+0+1=1+0+1
• So this number is divisible by 11.

• d)1210121= 1+1+1+1= 2+0+2
• So this number is divisible by 11.

• e)758043 = 7+8+4=5+0+3
• So this number is not divisible by 11.

• f)8338472 = 8+3+4+2= 3+8+7
• So this number is not divisible by 11.

• g)54678 = 5+6+8=4+7
• So this number is not divisible by 11.

• h)13431 = 1+4+1 = 3+3
• So this number is divisible by 11.

• i)423423 = 4+3+2= 2+4+3
• So this number is divisible by 11.

• j)168861​ =  1+8+6​= 6+8+1​
• So this number is divisible by 11.

Answer:

              So the numbers divisible by 11 are a, b, c, d, h, i, j.