一根竹竿直插入水底，竹竿湿了40厘米， 把一根竹竿垂直插入水底，竹竿湿了40厘米，将竹竿倒过来插入水...
\u628a\u4e00\u6839\u7af9\u7aff\u5782\u76f4\u63d2\u5165\u6c34\u5e95\uff0c\u7af9\u7aff\u6e7f\u4e8640\u5398\u7c73\uff0c\u7136\u540e\u5c06\u7af9\u7aff\u8f6c\u8fc7\u6765\u63d2\u5165\u6c34\u5e95\uff0c\u8fd9\u65f6\u7af9\u7aff\u6e7f\u7684\u90e8\u5206\u6bd4\u5b83\u7684\u4e00\u534a\u957f13\u5398\uff0840\u00d72-13\uff09 \u00f7 1 2 \uff0e=67\u00d72\uff0c=134\uff08\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u7af9\u7aff\u957f134\u5398\u7c73\uff0e\u6545\u7b54\u6848\u4e3a\uff1a134\uff0e
\uff0840+40-13\uff09\u00f71/2
=67\u00f71/2
=134\u5398\u7c73
\u7af9\u7aff\u957f134\u5398\u7c73
则40+40=X×2/3 -12
92=2X/3
X=92×3÷2
X=138厘米=1.38米
若有疑问可以百度Hi、
解：设竹竿长x cm
40+40=2/3x-12
x=138cm
138cm=1.38m
答：竹竿长1.38m
设全长是x,
则可列方程：40+40=2/3X-12
X=138厘米
设全长X米
2X/3-12=80
2X/3=92
X=138
竹竿全长1.38米
绛旓細鍥犱负绗簩娆℃箍鐨勫湴鏂规瘮瀹冪殑2/3灏12鍘樼背锛岃鏄庣浜屾婀跨殑闀垮害灏忎簬绔圭鎬婚暱銆傛墍浠ワ紝40鍘樼背绛変簬鎬婚暱鐨2/3鍑忓幓12鍘樼背锛(40+12)梅2/3=52脳3/2=78锛岀绔挎婚暱78鍘樼背銆
绛旓細瑙ｏ細璁绔圭鍏ㄩ暱涓篨鍘樼背 鍒40+40=X脳2/3 -12 92=2X/3 X=92脳3梅2 X=138鍘樼背=1.38绫 鑻ユ湁鐤戦棶鍙互鐧惧害Hi銆
绛旓細璁惧叏闀夸负x鍘樼背 1/2x+13=40脳2 1/2x=67 x=144 绔圭鍏ㄩ暱144鍘樼背
绛旓細鍥炵瓟锛40-13=27CM,27梅2鍒嗕箣1=54
绛旓細姘存繁灏辨槸40锛屾墍浠ヤ袱娆″氨鏄40+404=80cm
绛旓細璁惧叏闀夸负x鍘樼背 1/2x-13=40*2 1/2x=93 x=186 绔圭鍏ㄩ暱186鍘樼背
绛旓細瑙ｅ緱绔圭闀跨殑涓鍗婁负40鍔40鍑6.5绛変簬73.5锛坈m锛锛岀绔闀73.5涔2绛変簬147锛坈m 锛夋眰閲囩撼鎵撳瓧瓒呯疮
绛旓細璁绔圭闀 x 绫炽80 - x/2 = 6.5 160 - x = 13 x = 147 鍘樼背
绛旓細绗簩娆′篃婀夸簡40鍘樼背,鍏辨箍浜80鍘樼背,绔圭婀鐨勯儴鍒嗘瘮瀹冪殑1/2灏13鍘樼背,鎵浠ュ叏閮ㄧ殑涓鍗婃槸93鍘樼背 鍏ㄩ暱186鍘樼背.
绛旓細璁绔圭闀垮害涓篨cm X/2+13=40 X=54
