Question

Write the smallest digit and the greatest digit in the blank space of $\_\_6724$, so that the number is divisible by $3$.

Answer 1

Step $1:$ Finding the smallest digit:

Divisibility of $3$: A number is divisible by $3$, when the sum of the digits of the number is divisible by $3$

The given number is $\_\_6724$

Sum of the given digits $6+7+2+4=19$

$19$ is not divisible by $3$

The smallest number greater than $19$ and divisible by $3$ is $21$

Therefore, the smallest digit is $21$$-$$19$$=$$2$

Step $2:$ Finding the greatest digit:

Now, for greatest digit, the sum should be greatest and divisible by $3$

Therefore, the greatest sum is $27$

Thus, the greatest digit is $27$$-$$19$$=$$8$

Hence, the smallest digit is $2$ and the greatest digit is $8$.