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 $11$.