Four digit numbers formed with 1, 2, 4, 6, and 8 without repetition are formed in ascending order and ranked. Then the rank of 4618 is

Ascending order of given digits : 12468To find rank of 4618, out of four digit numbers without repetion in ascending orderThe number of four digit numbers                       starting with 1      = P3  4        ''       ''   2      = P3  4        ''       ''   41    = P2  3        ''       ''   42    = P2  3First number starting with 46 is 4612, and the next number is 4618.Rank of 4618 = 2×4P3 + 2×3P2 + 1 + 1 = 62