Question

$7x34\text{divisible by 9 ?}$

Answer 1

$\because 7x34\text{is multiple of 9}\Rightarrow 7+x+3+4\text{is a multiple of 9}\Rightarrow 14+x=0,9,18,27,....\Rightarrow x=-1,4,13,....\text{Since, x is a digit}\therefore x=4$