Question

Using the divisibility test, determine $12159$ is divisible by $4$, by $8$ or not?

Answer 1

Step $1:$ Explaining the divisibility test:

Divisibility test of $4$: A number is divisible by $4$, when the last two digits of the number is divisible by $4$

Divisibility test of $8$: A number is divisible by $8$, when the last three digits of the number is divisible by $8$

Step $2$: Finding whether $12159$ is divisible by $4$, by $8$ or not

The given number is $12159$

Last two digits in $12159$ is $59$

Clearly, $59$$÷4=$$14.75$

Thus, $59$ is not divisible by $4$, therefore $12159$ is not divisible by $4$

Last three digits in $12159$ is $159$

Clearly, $159$$÷8=$$19.875$

Thus, $159$ is not divisible by $8$,therefore $12159$ is not divisible by $8$

Hence, $12159$ is not divisible by both $4$ and $8$