Question

Using divisibility tests, determine the following number is divisible by $$11$$.
$$7138965$$.

Answer 1

Sum of the digits at odd places$$=5+9+3+7=24$$
Sum of the digits at even places$$=6+8+1=15$$
Difference $$=24-15=9$$
The difference between the sum of the digits at odd places and the sum of digits at even places is $$9$$, which is not divisible by $$11$$. Therefore, $$7138965$$ is not divisible by $$11$$.