从0到9这十个数字中任选5个,组成没有重复的五位数,这五位数是奇数的概率是多少? 从0到9的十个数字中选5个数字,组成没有重复的五位数且被5整...
\u4ece0\u52309\u8fd910\u4e2a\u6570\u5b57\u4e2d,\u9009\u51fa5\u4e2a\u6570\u5b57\u7ec4\u6210\u6ca1\u6709\u91cd\u590d\u6570\u5b57\u7684\u4e94\u4f4d\u6570,\u6c42\u767e\u4f4d\u6570\u5b57\u662f0\u7684\u6982\u7387P(5,9) -----5\u4f4d\u6570\u4e2d\u6ca10\u7684\u60c5\u51b5
P(4,9)*4 -----5\u4f4d\u6570\u4e2d\u67090\u7684\u60c5\u51b5
P(4,9) -----\u767e\u4f4d\u6570\u5b57\u662f0\u7684\u60c5\u51b5
P(4,9)/[P(5,9)+P(4,9)*4]=9*8*7*6/(9*8*7*6*5+9*8*7*6*4)=1/9
1. \u7ec4\u6210\u6ca1\u6709\u91cd\u590d\u7684\u4e94\u4f4d\u6570\u4e14\u88ab5\u6574\u9664
\u4e2a\u4f4d\u5fc5\u987b\u662f5\u62160
(1)\u4e2a\u4f4d\u662f5\u65f6\uff0c\u4e07\u4f4d\u4e0d\u80fd\u662f0\uff0c\u6240\u4ee5\u6709A(8,1)*A(8,3)
(2)\u4e2a\u4f4d\u662f0\u65f6\uff0c\u5176\u4ed64\u4e2a\u6570\u5b57\u53ef\u4efb\u9009\uff0c\u6240\u4ee5\u6709A(9,4)
\u5171\u6709\uff1aA(8,1)*A(8,3)+A(9,4)=8*8*7*6+9*8*7*6
=8*7*6*(9+8)=5712
2. \u6ca1\u6709\u91cd\u590d\u7684\u4e94\u4f4d\u5076\u6570
\u4e2a\u4f4d\u5fc5\u987b\u662f0\uff0c2\uff0c4\uff0c6\uff0c8
(1)\u4e2a\u4f4d\u662f0\u65f6\uff0c\u6709A(9, 4)
(2) \u4e2a\u4f4d\u4e0d\u662f0\u65f6\uff0c\u9996\u4f4d\u4e0d\u80fd\u662f0\uff0c\u6709A(4,1)*A(8,1)*A(8,3)
\u5171\u6709=A(9,4)+A(4,1)*A(8,1)*A(8,3)=9*8*7*6+4*8*8*7*6
=8*7*6*(9+32)
=13776
是奇数的,有:5×8×8×7×6种
所求概率为:(5×8×8×7×6)÷(9×9×8×7×6)=40/81
8*8*7*6*5/(9*9*8*7*6)=40/81。是奇数各位只有五种可能,万位又不能为零,所以只有八种可能,其余的根据不能重复,依次减一,明白了吗?
40/81
绛旓細鑳界粍鎴愮殑5浣嶆暟锛屼竴鍏辨湁锛9脳9脳8脳7脳6绉 鏄鏁扮殑锛屾湁锛5脳8脳8脳7脳6绉 鎵姹傛鐜囦负锛(5脳8脳8脳7脳6锛壝(9脳9脳8脳7脳6)=40/81
绛旓細鍥犱负涓鍏辨湁10涓暟瀛锛屽垯涓鍏卞彲浠ョ粍鎴10脳10脳10脳10脳10脳10=1000000涓笉鍚岀殑鍏綅鏁帮紝 鍒欏叾涓壒绛夊鍙风爜鏄010019鍑虹幇鐨勫彲鑳芥ф槸1梅1000000= 1 1000000 锛 绛旓細涓壒绛夊鐨勬鐜囨槸 1 1000000 锛 鏁呴夛細C锛
绛旓細10鐨勪簲娆℃柟銆旂涓浣嶆湁鍗佺鍙兘锛堝垎鍒槸0鍒9锛夌浜屻佷笁銆佸洓銆佷簲浣嶆暟涔熶竴鏍凤紝鎵浠浜斾釜鍗佺浉涔樺氨鏄崄鐨勪簲娆℃柟銆
绛旓細鍥炵瓟锛氭垜璁や负浜斾釜閮戒负濂囨暟鐨勫彲鑳芥т篃璁镐负浜岀櫨浜斿崄浜屽垎涔嬩竴銆傝屽伓鏁扮殑鍑犵巼鏇村皬銆
绛旓細6825 鑳借3,5,7,13鏁撮櫎 3脳5脳7脳13=1365 1365脳13=17745锛堟湁閲嶅鐨鏁帮紝涓嶅 1365脳7 =9555锛堟湁閲嶅鐨勬暟锛屼笉瀵 1365脳5=6825鍙互
绛旓細鐢遍鐭ワ紝鍙25鏁撮櫎鐨勬暟鍏舵渶鍚庝袱浣嶆暟蹇呯劧鏄25銆50銆75锛屽悓鏃0涓嶈兘鍦ㄧ涓浣嶃傚氨浠5浣嶆暟涓轰緥鍚с浠0-9鍗佷釜鏁颁腑浠婚5涓缁勬垚5浣嶆暟鐨勬诲拰鏈夛紝(C91)*(C91)*(C81)*(C71)(C61)锛堝叾涓紙C91锛夎〃绀轰粠9涓暟涓1涓紝鍏朵粬渚濇绫绘帹锛夊綋灏炬暟涓25鏃讹紝绗﹀悎姝ゆ潯浠剁殑鏁版湁锛岋紙C71锛*锛圕71锛*锛圕61锛...
绛旓細鑰冭檻鏁板瓧鍙噸澶嶏紝鏈98缁 {{0,0,2,9,9},{0,0,3,8,9},{0,0,4,7,9},{0,0,4,8,8},{0,0,5,6,9},{0,0,5,7,8},{0,0,6,6,8},{0,0,6,7,7},{0,1,1,9,9},{0,1,2,8,9},{0,1,3,7,9},{0,1,3,8,8},{0,1,4,6,9},{0,1,4,7,8},{0,1,...
绛旓細杩欎釜鏁鏈澶ф槸94185銆傝瘉鏄庯細棣栧厛锛岀敱浜3銆5銆7銆13閮芥槸璐ㄦ暟锛屽洜姝よ浣杩欎釜5浣嶆暟鑳借杩欏嚑涓暟鍚屾椂鏁撮櫎锛岄偅涔堣繖涓5浣嶆暟涓瀹氳鑳借3*5*7*13锛1365鏁撮櫎锛屽嵆褰㈠1365n,鍏朵腑n涓烘暣鏁般傜敱浜99999/1365鐨勬暣鏁伴儴鍒嗘槸73锛屽洜姝5浣嶆暟涓兘琚1365鏁撮櫎鐨勬渶澶х殑鏁颁负n=73鏃剁殑1365*73=99645锛屼絾鏄繖涓鏁颁腑鏈変袱浣嶉兘...
绛旓細鍒嗕袱绉嶆儏鍐 1.缁勬垚鐨勭粍鏄嚜鐒鏁,鍗抽浣嶅繀椤讳笉涓0 (1)鍙噸澶嶇殑鎯呭喌涓 闄や簡绗竴浣嶆湁9绉嶉夋嫨澶,鍏朵綑4浣嶉兘鏈10绉嶉夋嫨 鏁呮湁9*10*10*10*10=90000缁 (2)涓嶅彲閲嶅鐨勬儏鍐典笅 闄や簡绗竴浣嶆湁9绉嶉夋嫨澶,鏁呮湁9*9*8*7*6=27216缁 2.鍙鎴愮粍鍗冲彲,鍗抽浣嶅彲浠ヤ负0 (1)鍙噸澶嶇殑鎯呭喌涓 闄や簡绗竴浣嶆湁...
绛旓細1. 缁勬垚娌℃湁閲嶅鐨浜浣嶆暟涓旇5鏁撮櫎 涓綅蹇呴』鏄5鎴0 (1)涓綅鏄5鏃讹紝涓囦綅涓嶈兘鏄0锛鎵浠ユ湁A(8,1)*A(8,3)(2)涓綅鏄0鏃讹紝鍏朵粬4涓暟瀛鍙浠婚夛紝鎵浠ユ湁A(9,4)鍏辨湁锛欰(8,1)*A(8,3)+A(9,4)=8*8*7*6+9*8*7*6 =8*7*6*(9+8)=5712 2. 娌℃湁閲嶅鐨勪簲浣嶅伓鏁 涓綅蹇呴』鏄0锛...