Mymensingh secondary 2017 #6
Posted: Sun Feb 17, 2019 3:34 pm
$x$ is a positive integer such that its digits can only be $3,4,5,6$. $x$ contains at least one copy of each of these four digits. The sum of the digits of $x$ is $900$ and the sum of the digits of $2x$ is also $900$. How many digits are there in the minimum value of $x$?