Can i ask, err this manga called Golden time, is it ended in chapter 51 ?

it say it ended in volume 9

the translated was up to chapter 30 at volume 6

seeing 1 chapter was nearly 30-40 pages, i think 21 chapter is enough to cover to 3 volumes so 6+3=9 volumes ?

or there's another chapter ?

because i found the end was really different than the anime end(people say the ending was same in both novel, anime and manga)

I remember seeing the manga raws before. If I remember correctly it ended basically the same way as the anime. In the anime I think they added the parade he participated in where he has a breakdown when all his memories suddenly returned to make it more dramatic right before he returned to his home in the end.