What least value must be assigned to * so that the number 197*5462 is divisible by 9?
Soln:
Let the missing digit be x.
Sum of digits = (1+9+7+x+5+4+6+2) = (34+x)
For (34+x) to be divisible by 9, x must be replaced by 2.
Hence, the digits in place of * must be 2