设长方形的宽为n,则长为(7/5)n,设正方形的边长为m则2×((7/5)n+n)÷4m=6/5n=m所以面积比为(n×(7/5)n)÷(n×n)=7/5
长方形周长为6a,正方形周长为5a宽:3a/(1+7/5)=5/4a长:5a/4*7/5=7/4a正方形边长5a/4长方形与正方形的面积比=5/4a*7/4a:5/4a*5/4a=7:5
设:长方形的宽为x,则长为7x/5,正方形边长为y2(7x/5+x)/4y=6/5x=2yS1:S2=7x^2/5:y^2=28:5