Question

Find the least value that must be given to number $a$ so that the number $91876a2$ is divisible by $8$.

Answer 1

Apply the divisibility test of $8$ for the given statement.

If a number is divisible by $8$, then last three digits of that number are divisible by $8$.

So, the value of $a$ varies from $0$ to $9$.

If $a=0$, then $6a2=602$, which is not divisible by $8$.

If $a=1$, then $6a2=612$, which is not divisible by $8$.

If $a=2$, then $6a2=622$, which is not divisible by $8$.

If $a=3$, then $6a2=632$, which is divisible by $8$.

So, the least value required is $3$.

Hence, the least value that must be given to number $a$ so that the number $91876a2$ is divisible by $8$ is $3$.