Question

Test the divisibility of the following numbers by 11:

(i) 5335
(ii) 70169803
(iii) 10000001

Answer 1

(i) The given number is 5,335.
The sum of the digit at the odd places = 5 + 3 = 8
The sum of the digits at the even places = 3 + 5 = 8
Their difference = 8 − 8 = 0
∴ 5,335 is divisible by 11.

(ii) The given number is 7,01,69,803.
The sum of the digit at the odd places = 7 + 1 + 9 + 0 = 17
The sum of the digits at the even places = 0 + 6 + 8 + 3 = 17
Their difference = 17 − 17 = 0
∴ 7,01,69,803 is divisible by 11.

(iii) The given number is 1,00,00,001.
The sum of the digit at the odd places = 1 + 0 + 0 + 0 = 1
The sum of the digits at the even places = 0 + 0 + 0 + 1 = 1
Their difference = 1 − 1 = 0
∴ 1,00,00,001 is divisible by 11.