$n$-digit numbers are formed using only three digits 2, 5 and 7. The smallest value of $n$ for which 900 such distinct numbers can be formed is : (1) 9 (2) 7 (3) 8 (4) 6
$n$-digit numbers are formed using only three digits 2, 5 and 7. The smallest value of $n$ for which 900 such distinct numbers can be formed is :\\
(1) 9\\
(2) 7\\
(3) 8\\
(4) 6