Write a digit in the blank space of , so that the number is divisible by .
Finding the digit:
Divisibility of : A number is divisible by , if the difference between the sum of the digits at even places and the sum of the digits at odd places(starting from the ones place) is , or divisible by .
Consider the number
Sum of the digits at odd places =
Sum of the digits at even places =
Therefore, the difference either should be equal to or should be divisible by
or
Since, is not a digit,
Hence, the required digit is