mot hinh chu nhat co chu vi 120 m. neu tang chieu rong cua hinh chu nhat do them 10% va giam chieu dai di 10%thi ta duoc 1 hinh vuong .hoi:

a, chieu rong sau khi tang bang bao nhieu phan tram chieu rong ban dau

    chieu dai sau khi giam bang bao nhieu phan tram chieu dai ban dau

b, tinh dien tich hinh chu nhat do.

1 Hinh hop chu nhat co chieu dai 1m 5 cm chieu rong bang 80 phan tram chieu dai chieu cao bang 75 phan tram chieu rong hoi doen tich toan phan cua hinh hop do a bao nhieu met vuong

2 hinh hop chu nhatvco chieu dai 25 cm chieu cao 18 cm chu vi mat day 80 cm tinh dien tich toan phan cua hin do

Mot hinh chu nhat co chieu rong bang 18,75 % chu vi cua hinh do.ti so phan tram cua chieu rong va chieu dai cua hinh chu nhat da cho la bao nhieu phan tram

mot khu rung hinh chu nhat co chu vi 3,5 km va chieu dai gap ruoi chieu rong hoi khu rung do co dien tich bang bao nhieu met vuong bao nhieu hec ta

chu vi hinh chu nhat la 18 cm.neu giam CD 20 phan tram , tang CR 25 phan tram . tinh dien tich hinh chu nhat

cho 1 HCN co chu vi la 5m, biet CD gap ruoi CR vay S cua HCN do la bao nhiu xang ti met vuong? can gap help me

Tinh dien tich xung quanh dien tich toan phan va the tich cua hinh hop chu nhat  biet cd la 5/6m cr bang 3/4 cd  cc gap doi cr

1 phong hoc dang hinh hop chu nhat co CD 8 m, CR 6m , CCao bang 2/3 CR .hoi phong hoc do chua duoc bao nhieu met khoi khong khi , biet rang the tich cua cac do vat trong phong la 3met khoi

cau 1 : mot cua hang ban lai 20% so voi gia ban . Hoi cua hang lai bao nhieu phan tram so voi gia von

cau 2 : de dien tich mot hinh chu nhat tang len gap doi ma chieu rong chi tang them 25% thi chieu dai phai tang them bao nhieu phan tram 

cau 3 : neu giam do dai canh cua mot hinh vuong di 10% thi dien tich cua hinh vuong do giam di bao nhieu phan tram

cau 4 : neu tang do dai canh cua mot hinh vuong them 10% thi dien tich cua hinh vuong do tang them bao nhieu phan tram