1樓：匿名使用者
只有3種形態 aab abc aaa
2樓：匿名使用者
1000種。從000到999
0到9的所有數字排成3位數的有多少種，全排出來
3樓：珠山龍少
0不能排在百位，其他的任意排，總共有9*10*10=900種，
100,101,102,103,104,105,106,107,108,109,
110,111,112,113,114,115,116,117,118,119,
120,121,122,123,124,125,126,127,128,129,
130,131,132,133,134,135,136,137,138,139,
140,141,142,143,144,145,146,147,148,149,
150,151,152,153,154,155,156,157,158,159,
160,161,162,163,164,165,166,167,168,169,
170,171,172,173,174,175,176,177,178,179,
180,181,182,183,184,185,186,187,188,189,
190,191,192,193,194,195,196,197,198,199,
200,201,202,203,204,205,206,207,208,209,
210,211,212,213,214,215,216,217,218,219,
220,221,222,223,224,225,226,227,228,229,
230,231,232,233,234,235,236,237,238,239,
240,241,242,243,244,245,246,247,248,249,
250,251,252,253,254,255,256,257,258,259,
260,261,262,263,264,265,266,267,268,269,
270,271,272,273,274,275,276,277,278,279,
280,281,282,283,284,285,286,287,288,289,
290,291,292,293,294,295,296,297,298,299,
300,301,302,303,304,305,306,307,308,309,
310,311,312,313,314,315,316,317,318,319,
320,321,322,323,324,325,326,327,328,329,
330,331,332,333,334,335,336,337,338,339,
340,341,342,343,344,345,346,347,348,349,
350,351,352,353,354,355,356,357,358,359,
360,361,362,363,364,365,366,367,368,369,
370,371,372,373,374,375,376,377,378,379,
380,381,382,383,384,385,386,387,388,389,
390,391,392,393,394,395,396,397,398,399,
400,401,402,403,404,405,406,407,408,409,
410,411,412,413,414,415,416,417,418,419,
420,421,422,423,424,425,426,427,428,429,
430,431,432,433,434,435,436,437,438,439,
440,441,442,443,444,445,446,447,448,449,
450,451,452,453,454,455,456,457,458,459,
460,461,462,463,464,465,466,467,468,469,
470,471,472,473,474,475,476,477,478,479,
480,481,482,483,484,485,486,487,488,489,
490,491,492,493,494,495,496,497,498,499,
500,501,502,503,504,505,506,507,508,509,
510,511,512,513,514,515,516,517,518,519,
520,521,522,523,524,525,526,527,528,529,
530,531,532,533,534,535,536,537,538,539,
540,541,542,543,544,545,546,547,548,549,
550,551,552,553,554,555,556,557,558,559,
560,561,562,563,564,565,566,567,568,569,
570,571,572,573,574,575,576,577,578,579,
580,581,582,583,584,585,586,587,588,589,
590,591,592,593,594,595,596,597,598,599,
600,601,602,603,604,605,606,607,608,609,
610,611,612,613,614,615,616,617,618,619,
620,621,622,623,624,625,626,627,628,629,
630,631,632,633,634,635,636,637,638,639,
640,641,642,643,644,645,646,647,648,649,
650,651,652,653,654,655,656,657,658,659,
660,661,662,663,664,665,666,667,668,669,
670,671,672,673,674,675,676,677,678,679,
680,681,682,683,684,685,686,687,688,689,
690,691,692,693,694,695,696,697,698,699,
700,701,702,703,704,705,706,707,708,709,
710,711,712,713,714,715,716,717,718,719,
720,721,722,723,724,725,726,727,728,729,
730,731,732,733,734,735,736,737,738,739,
740,741,742,743,744,745,746,747,748,749,
750,751,752,753,754,755,756,757,758,759,
760,761,762,763,764,765,766,767,768,769,
770,771,772,773,774,775,776,777,778,779,
780,781,782,783,784,785,786,787,788,789,
790,791,792,793,794,795,796,797,798,799,
800,801,802,803,804,805,806,807,808,809,
810,811,812,813,814,815,816,817,818,819,
820,821,822,823,824,825,826,827,828,829,
830,831,832,833,834,835,836,837,838,839,
840,841,842,843,844,845,846,847,848,849,
850,851,852,853,854,855,856,857,858,859,
860,861,862,863,864,865,866,867,868,869,
870,871,872,873,874,875,876,877,878,879,
880,881,882,883,884,885,886,887,888,889,
890,891,892,893,894,895,896,897,898,899,
900,901,902,903,904,905,906,907,908,909,
910,911,912,913,914,915,916,917,918,919,
920,921,922,923,924,925,926,927,928,929,
930,931,932,933,934,935,936,937,938,939,
940,941,942,943,944,945,946,947,948,949,
950,951,952,953,954,955,956,957,958,959,
960,961,962,963,964,965,966,967,968,969,
970,971,972,973,974,975,976,977,978,979,
980,981,982,983,984,985,986,987,988,989,
990,991,992,993,994,995,996,997,998,999,900
0--9全部的數字任意組合成3位數，能組多少個。分別是什麼
4樓：匿名使用者
解：百位不能為0，所以有8種可能
十位有9種可能，個位有8種
所以一共8×9×8=576種
我是老師 謝謝採納
5樓：匿名使用者
能組成504組，分別是什麼，你自己慢慢寫了，這裡寫太麻煩了，也太多了
6樓：信石
百位9種（123456789），十位9種，各位8種。
9*9*8=648種。
有0到9這幾個數字，組成三位所有的號碼，有誰能說全 10
7樓：匿名使用者
沒說不可以重複，000~999共一千個號碼
8樓：匿名使用者
排列組合啊可我不會……
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