=d÷2 s=πr的平方 c=2πr
=1÷2 =3.14×0.5×0.5 =2×3.14×0.5
=0.5(m) =0.785(m的平方) =3.14(m)
答:这张圆桌的面积是0.785m的平方,花边长3.14m