Question

If the three-digit number 24x is divisible by 9, what is the value of x?

Answer 1

Since 24x is divisible by 9, sum of its digits, i.e., 2 + 4 + x should be divisible by 9, i.e., 6 + x should be divisible by 9.

This is possible when 6 + x = 9 or 18, ....

But, since x is a digit, therefore, 6 + x = 9, i.e., x = 3.