Question

the area of the rectangle is x if the length of the rectangle is increased by 20% and the width of the rectangle is decreased by 10%, the area of the rectangle is increased by 20 m2 find x

Answer 1

the area of the rectangle aftter the length of the rectangle is increased by 20% is :

\(x.\left(100\%+20\%\right)=x.120\%\)

the area of the rectangle aftter the width of the rectangle is decreased by 10% is :

\(x.120\%.\left(100\%-10\%\right)=x.120\%.90\%=x.108\%\)

so   the area of the rectangle is increased by 20 m2 equivalent \(x.8\%\)

\(\Rightarrow x=20:8\%=250\)m2

Answer 2

dịch ra tiếng việt được ko

Answer 3

diện tích hình chữ nhật là x nếu tăng chiều dài 20% và giảm chiều rộng 10% thì diện tích hình chữ nhật tăng thêm 20 m2 tìm x