Question

$3x26\text{a multiple of 6 ?}$

Answer 1

$\because 3x26\text{is a multiple of 6}3+x+2+6\text{is a multiple of 3}\Rightarrow 11+x=0,3,6,9,12,15,18,21,....\Rightarrow x=-11,-8,-5,-2,1,4,7,10,....\text{Since, x is a digit}\therefore x=1,4or7$