HELP...me...

HELP...me...
1.y is _9_ of x.what percentage of x is
25
rhe required percentage=_______×_______%
=_________
2.in a basketball team of a youth club,25%of team are of age twelve,_2_of them are of age thirteen and rest are of age fourteen.what
5 percentage of the team is of age fuorteen?
3.calculate(12%+8%)×16%÷8%.
4.there are 6arts books in a bookcase.the numbers of arts books in thet bookcase is25%thet of scientific fictions,and the number of scientfic fictions is40%of the whole number of books.how many books ae in the bookcase?
let x be the whole number of books.
number of scientific fiction = x ×________
number of arts books = 25% ×______________= 6
x =_____________
∴there are _________books in the bookcase.
第二题是五分之二