Question

Test the divisibility of the following number by $$11:$$
$$8790322$$

Answer 1

If the difference of the sum of its digits at odd places and sum of its digits at even places is either $$0$$ or multiple of $$11$$ then the given number is divisible by $$11$$
$$8790322$$
Sum of the digits at odd places $$= 2 + 3 + 9 + 8 = 22$$
Sum of the digits at even places $$= 2 + 0 + 7 = 9$$
Difference of the two sums $$= 22 - 9 = 13$$
$$\therefore 8790322$$ is divisible by $$11$$