Question

In each of the following numbers replace M by the smallest whole number to make the resulting number divisible by $9$.
(i) $76M91$

Answer 1

Step: Find the value of M
Given number: $76M91$
A number is divisible by $9$ if the sum of its digit is divisible by $9$.
Here, the sum of digits =$7$+$6$+$M$+$9$+$1$
=$23$+$M$
The number next to $23$ which is divisible by $9$ is $27$.
So, the required number =$27$−$23$
Hence, the value of $M$ = $4$.