Explanation:

Given that,
6913 x 08
The given number will be divisible by 88 if it will be individually divisible by 11 and 8.
Divisibility of 8:
Any number is divisible by 8 if the last three digits of that number will be divisible by 8.
the minimum possible value for which it is divisible by 8 is x=0,2,4,6,8
Divisibility by 11:
A number is divisible by 11 if we subtract and then add the digits in an alternate pattern from left to right, if it is either 0 or 11, then it
will be divisible by 11 otherwise not.

⇒ 6913x08

⇒ (8 + x + 1 + 6) − (0 + 3 + 9) = 15 − 12 + x = 3 + x

There is only one value for which both are satisfying the condition, which is x=8.
Hence, the number will be 6913808.
Hence, the minimum value of x should be 8.