Math圓周
回答 (3)
2010-06-05 5:50 am
✔ 最佳答案
Let r be the radius of the circle2X3.14Xr+2Xr=51.4
6.28Xr+2Xr=51.4
r(6.28+2)=51.4
rX8.28=51.4
r=51.4/8.28
so, the diameter is 51.4/8.28X2=12.4(cor to 3 sig.fig)
p.s:直徑=diameter
半徑=radius
2010-06-06 3:56 am
(3.14/2)d+d=51.4
2.57d=51.4
d=20
2.57d=51.4
d=20
2010-06-05 5:44 am
假設直徑是X
X + X * 3.14 /2 =51.4
X * ( 1+1.57) =51.4
X = 20
X + X * 3.14 /2 =51.4
X * ( 1+1.57) =51.4
X = 20
收錄日期: 2021-04-29 15:44:10
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100604000051KK01328