The total number of two birds is only:
(590+5 10)/(9+ 1) = 1 10;
A bird with nine heads and one tail,
The number of nine-headed birds = (590-110)/(9-1) = 60;
Kyubi no Youko birds have a Kyubi no Youko head, and the number of Kyubi no Youko birds = 1 10-60 = 50.