Number System Practice Test 6

Divisibility rule of 3 is: if the sum of digits of a number is divisible by 3, then the number is also divisible by 3.
Now, 8 + 7 + x + 3 + 9 + 2 + x + 0 + 1 = 30 + 2x
substitute x= 9
30 + 2 × 9 = 30 + 18 = 36 divisible by 9
Hence, the largest possible value of x = 9.