王阿姨沿着一条河用篱笆围一个长27米，宽9米的长方形菜地，最少需要准备多长的篱笆
\u738b\u963f\u59e8\u6cbf\u7740\u4e00\u6761\u6cb3\u7528\u7bf1\u7b06\u56f4\u4e00\u4e2a\u957f27\u7c73\uff0c\u5bbd9\u7c73\u7684\u957f\u65b9\u5f62\u83dc\u5730\uff0c\u6700\u5c11\u9700\u8981\u51c6\u5907\u591a\u957f\u7684\u7bf1\u7b0627+2\u00d79=27+18=45\uff08\u7c73\uff09\uff0e\u7b54\uff1a\u6700\u5c11\u9700\u8981\u51c6\u590745\u7c73\u957f\u7684\u7bf1\u7b06\uff0e
\u89e3\uff1a\u5df2\u77e5\u738b\u5927\u5988\u6cbf\u7740\u4e00\u6761\u6cb3\u7528\u7bf1\u7b06\u56f4\u4e00\u4e2a\u957f25\u7c73\uff0c\u5bbd10\u7c73\u7684\u957f\u65b9\u5f62\u83dc\u5730\uff0c
\uff081\uff09\u82e5\u662f\u957f\u6cbf\u7740\u6cb3\u8fb9\uff0c
\u5f97\u7bf1\u7b06\u957f\u5ea6=\u957f+\u5bbd\u00d72
=25+10\u00d72
=25+20
=45\u7c73
\uff082\uff09\u82e5\u662f\u5bbd\u6cbf\u7740\u6cb3\u8fb9\uff0c
\u5f97\u7bf1\u7b06\u957f\u5ea6=\u957f\u00d72+\u5bbd
=25\u00d72+10
=50+10
=60\u7c73
\u5373\u6700\u5c11\u9700\u8981\u51c6\u590745\u7c73\u957f\u7684\u7bf1\u7b06\u3002
| 27+2×9 =27+18 =45（米）． 答：最少需要准备45米长的篱笆． |
绛旓細锛19-15锛壝2=2 15脳2=30 杩欎釜缇婂湀鐨勯潰绉槸30骞虫柟绫炽
绛旓細鐜嬮樋濮ㄧ敤闀27绫崇殑绡辩瑔涓轰簡涓涓浮鍦,闀11绫,瀹藉灏戠背锛熻В锛氭牴鎹鎰忓垪寮忎负锛27梅2-11 =13.5-11 =2.5锛堢背锛夌瓟锛氬2.5绫炽
绛旓細22x16=352骞虫柟绫 (22+16)x2=76绫
绛旓細鑿滃湴鐨勫崐寰勬槸锛18.84梅3.14=6锛堢背锛夎彍鍦扮殑闈㈢Н鏄細6²脳3.14梅2=56.52锛堝钩鏂圭背锛
绛旓細鍗婂緞=25.7/5.14=5绫 杩欏潡鑿滃湴鐨勯潰绉槸 5x5x3.14/2=39.25骞虫柟绫
绛旓細鍏堟眰鍑哄崐寰勶紝鍥犱负12.56鏄釜鍗婂渾锛屾墍浠12.56闄や互3.14=4绫筹紝闈㈢Н灏辨槸4鐨勫钩鏂逛箻浠3.12鍐嶉櫎浠2绛変簬25.12绫炽傞浮鑸嶉潰绉槸25.12
绛旓細鍗婂緞=18.84/3.14=6 闈㈢Н =3.14*6*6/2=56.52骞崇背
绛旓細濡傛灉澧欒冻澶熼暱锛屽垯鐢29绫崇殑绡辩瑔鍙互鍥存垚澶氱瀹藉害鐨勭緤鍦堬紝瀵瑰簲鏈夊绉嶉潰绉傛墍浠ユ湰棰樻病鏈夊敮涓鐨勮В銆
绛旓細涓ら潰闈犲锛屽洿鎴愯竟闀10绫崇殑姝ｆ柟褰紝闈㈢Н鏈澶с傝嫍鍦冮潰绉渶澶ф槸10脳10=100(骞虫柟绫)
绛旓細鍗犲湴= 蟺*6*6/2=18蟺 骞虫柟绫 鍛ㄩ暱= 2*6*蟺/2+12=6蟺+12 绫
