If 7x8 is exactly divisible by 9, then the least value of x is
We know that if sum of digits of a number is divisible by 9, then the number is divisible by 9.
Here,
7 + x + 8 = multiple of 9
15 + x = 0, 9, 18, …
Hence,
15 + x = 18
∴ x = 3
∴the least value of y is 3