Observation sequence 2 / 3, 3 / 7, 4 / 11, 1 / 3, x, 7 / 23, 8 / 27 Then the value of X should be 6 / 19. If it is arranged according to this rule, the 16th number is ()

Observation sequence 2 / 3, 3 / 7, 4 / 11, 1 / 3, x, 7 / 23, 8 / 27 Then the value of X should be 6 / 19. If it is arranged according to this rule, the 16th number is ()

three