mot thu vien co 10000quyen sach .Cu sau moi nam so sach cua thu vien lai duoc tang them 15%so voi nam truoc .Hoi sau hai nam thu vien do co tat ca bao nhieu quyen sach?

nguoi ta xep cac hlp co canh 1cm thanh 1hlp lon co s toan phan la 96cm2. Sau do nguoi ta son tat ca cac mat cua khoi lon do.Hoi bao nhieu hlp nho chi duoc son 3 mat? 2mat? 1 mat?Va ko duoc son mat nao?

nguoi ta xepp cac  hinh lap phuong nho nhu nhau thanh mot hinh lap phuong lon roi son tat ca cac mat cua hinh lap phuong do.Hoi co bao nhieu hinh lap phuong nho duoc son thanh 2 mat 

co tat ca 1800 vien gach nhu nhau duoc xep thanh hai chong gach . chong thu nhat co the tich bang 2/3 the tich chong thu hai. hoi moi chong gach co the tich bao nhieu met khoi

Mot thung hinh hop chu nhat lam bang ton,khong nap,co chieu dai la 1,2m,chieu rong 0,8, 5dm.Nguoi ta son tat ca  cac mat ngoai va mat trong cua thung.tinh dien tich duoc quet son .( do day ton khong dang ke)

co 27 khoi lap phuong nho bang nhau duoc ghep thanh mot hinh lap phuong lon . nguoi ta son tat ca cac mat cua hinh lap phuong lon do .

a] co.... khoi hinh lap phuong nho duoc son 3 mat .

b]co...khoi lap phuong nho duoc son 2 mat .

c]co .... khoi lap phuong nho duoc sin 1 mat.

d]co ... khoi lap phuong nho khong duoc son mat nao .

  GHI CA CACH GIAI NUA NHA . LAM ON , HELP ME 

y x 15 - y x 7 = 80

Lop 6A co 25 ban dang ki hoc ngoai khoa mon Van , 22 ban dang ki hoc ngoai khoa mon Toan , trong do co 7 ban dang ki hoc ca Van va Toan . Hoi

a, Co bao nhieu ban chi dang ki hoc Van ? chi dang ki hoc Toan ?

b, Lop 6A co bao nhieu hoc sinh

ban an lam mot cai hop dang hinh lap phuong bang bia co canh 10cm .

tinh the tich cai hop do .

neu dan giay mau tat ca cac mat mat ngoai cua hop do thi ban an can dung bao nhieu xang-ti-met vuong ?