bai4:an mua het 2/3 so tien an co,muavo het 3/4 so tien con lai sau khi mua sach va vo an con lai 3000 dong.Hoi an co bao nhieu tien?
bai5:mot can phong hinh chu nhat co chieu dai 8m,chieu rong bang 3/4 chieu dai.De lai nen can phong do,nguoi ta dung loai gach men hinh vuong canh 4dm.Hoi can phong duoc lat bang bao nhieu vien gach do ? (phan dien tich mach vua khong dang ke)
bai6:mot hinh thoi co hieu do hai duong cheo la muoi 1/5 m,ti so cuado dai duong cheo be va duong cheo lon la 2/5.Hoi hinh thoi do co dien tich la bao nhieu de-xi-met vuong
cac ban giup minh nhe
