一个三位数要能被2整除,那么三个数字之和一定要是2的倍数吗?

一个三位数要能被2整除,那么三个数字之和一定要是2的倍数吗?
一个三位数要能被2整除,那么三个数字之和一定要是2的倍数吗?

一个三位数要能被2整除,那么三个数字之和一定要是2的倍数吗?
不一定,如126能被2整除,而三个数字之和为9不是2的倍数.
只要末为数是二的倍数就能被2整除

偶数就能被2整除 但是这个三位数想加并不一定是偶数，也很可能是奇数

no

不是，如122

这个当然不是啦 ！！！
比如122，它可是被2整除
但是1+2+2=5，它却不是2的倍数哦

答案是---不是 假设这个数是 x*1000+y*100+c x不等于0
因为能被2整除所以 c是2的倍数
问 x+y+c是否一定是2的倍数 确定c是2的倍数
问题就变成x+y是否一定是2的倍数，因为x是1-9的自然数，y是0-9的数所以只有当x,y取值，同为奇数或者偶数是才会是2的倍数...

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答案是---不是 假设这个数是 x*1000+y*100+c x不等于0
因为能被2整除所以 c是2的倍数
问 x+y+c是否一定是2的倍数 确定c是2的倍数
问题就变成x+y是否一定是2的倍数，因为x是1-9的自然数，y是0-9的数所以只有当x,y取值，同为奇数或者偶数是才会是2的倍数

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一共有225个数能被动整除，但三个数之和不是二的倍数
NO
all are 1 no
NO
all are 2 no
NO
all are 3 no
NO
all are 4 no
NO
all are 5 no
110--0-1-1
112--2-1-1
114--4-1-1
116-...

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一共有225个数能被动整除，但三个数之和不是二的倍数
NO
all are 1 no
NO
all are 2 no
NO
all are 3 no
NO
all are 4 no
NO
all are 5 no
110--0-1-1
112--2-1-1
114--4-1-1
116--6-1-1
118--8-1-1
NO
all are 6 no
NO
all are 7 no
NO
all are 8 no
NO
all are 9 no
NO
all are 10 no
130--0-3-1
132--2-3-1
134--4-3-1
136--6-3-1
138--8-3-1
NO
all are 11 no
NO
all are 12 no
NO
all are 13 no
NO
all are 14 no
NO
all are 15 no
150--0-5-1
152--2-5-1
154--4-5-1
156--6-5-1
158--8-5-1
NO
all are 16 no
NO
all are 17 no
NO
all are 18 no
NO
all are 19 no
NO
all are 20 no
170--0-7-1
172--2-7-1
174--4-7-1
176--6-7-1
178--8-7-1
NO
all are 21 no
NO
all are 22 no
NO
all are 23 no
NO
all are 24 no
NO
all are 25 no
190--0-9-1
192--2-9-1
194--4-9-1
196--6-9-1
198--8-9-1
200--0-0-2
202--2-0-2
204--4-0-2
206--6-0-2
208--8-0-2
NO
all are 26 no
NO
all are 27 no
NO
all are 28 no
NO
all are 29 no
NO
all are 30 no
220--0-2-2
222--2-2-2
224--4-2-2
226--6-2-2
228--8-2-2
NO
all are 31 no
NO
all are 32 no
NO
all are 33 no
NO
all are 34 no
NO
all are 35 no
240--0-4-2
242--2-4-2
244--4-4-2
246--6-4-2
248--8-4-2
NO
all are 36 no
NO
all are 37 no
NO
all are 38 no
NO
all are 39 no
NO
all are 40 no
260--0-6-2
262--2-6-2
264--4-6-2
266--6-6-2
268--8-6-2
NO
all are 41 no
NO
all are 42 no
NO
all are 43 no
NO
all are 44 no
NO
all are 45 no
280--0-8-2
282--2-8-2
284--4-8-2
286--6-8-2
288--8-8-2
NO
all are 46 no
NO
all are 47 no
NO
all are 48 no
NO
all are 49 no
NO
all are 50 no
NO
all are 51 no
NO
all are 52 no
NO
all are 53 no
NO
all are 54 no
NO
all are 55 no
310--0-1-3
312--2-1-3
314--4-1-3
316--6-1-3
318--8-1-3
NO
all are 56 no
NO
all are 57 no
NO
all are 58 no
NO
all are 59 no
NO
all are 60 no
330--0-3-3
332--2-3-3
334--4-3-3
336--6-3-3
338--8-3-3
NO
all are 61 no
NO
all are 62 no
NO
all are 63 no
NO
all are 64 no
NO
all are 65 no
350--0-5-3
352--2-5-3
354--4-5-3
356--6-5-3
358--8-5-3
NO
all are 66 no
NO
all are 67 no
NO
all are 68 no
NO
all are 69 no
NO
all are 70 no
370--0-7-3
372--2-7-3
374--4-7-3
376--6-7-3
378--8-7-3
NO
all are 71 no
NO
all are 72 no
NO
all are 73 no
NO
all are 74 no
NO
all are 75 no
390--0-9-3
392--2-9-3
394--4-9-3
396--6-9-3
398--8-9-3
400--0-0-4
402--2-0-4
404--4-0-4
406--6-0-4
408--8-0-4
NO
all are 76 no
NO
all are 77 no
NO
all are 78 no
NO
all are 79 no
NO
all are 80 no
420--0-2-4
422--2-2-4
424--4-2-4
426--6-2-4
428--8-2-4
NO
all are 81 no
NO
all are 82 no
NO
all are 83 no
NO
all are 84 no
NO
all are 85 no
440--0-4-4
442--2-4-4
444--4-4-4
446--6-4-4
448--8-4-4
NO
all are 86 no
NO
all are 87 no
NO
all are 88 no
NO
all are 89 no
NO
all are 90 no
460--0-6-4
462--2-6-4
464--4-6-4
466--6-6-4
468--8-6-4
NO
all are 91 no
NO
all are 92 no
NO
all are 93 no
NO
all are 94 no
NO
all are 95 no
480--0-8-4
482--2-8-4
484--4-8-4
486--6-8-4
488--8-8-4
NO
all are 96 no
NO
all are 97 no
NO
all are 98 no
NO
all are 99 no
NO
all are 100 no
NO
all are 101 no
NO
all are 102 no
NO
all are 103 no
NO
all are 104 no
NO
all are 105 no
510--0-1-5
512--2-1-5
514--4-1-5
516--6-1-5
518--8-1-5
NO
all are 106 no
NO
all are 107 no
NO
all are 108 no
NO
all are 109 no
NO
all are 110 no
530--0-3-5
532--2-3-5
534--4-3-5
536--6-3-5
538--8-3-5
NO
all are 111 no
NO
all are 112 no
NO
all are 113 no
NO
all are 114 no
NO
all are 115 no
550--0-5-5
552--2-5-5
554--4-5-5
556--6-5-5
558--8-5-5
NO
all are 116 no
NO
all are 117 no
NO
all are 118 no
NO
all are 119 no
NO
all are 120 no
570--0-7-5
572--2-7-5
574--4-7-5
576--6-7-5
578--8-7-5
NO
all are 121 no
NO
all are 122 no
NO
all are 123 no
NO
all are 124 no
NO
all are 125 no
590--0-9-5
592--2-9-5
594--4-9-5
596--6-9-5
598--8-9-5
600--0-0-6
602--2-0-6
604--4-0-6
606--6-0-6
608--8-0-6
NO
all are 126 no
NO
all are 127 no
NO
all are 128 no
NO
all are 129 no
NO
all are 130 no
620--0-2-6
622--2-2-6
624--4-2-6
626--6-2-6
628--8-2-6
NO
all are 131 no
NO
all are 132 no
NO
all are 133 no
NO
all are 134 no
NO
all are 135 no
640--0-4-6
642--2-4-6
644--4-4-6
646--6-4-6
648--8-4-6
NO
all are 136 no
NO
all are 137 no
NO
all are 138 no
NO
all are 139 no
NO
all are 140 no
660--0-6-6
662--2-6-6
664--4-6-6
666--6-6-6
668--8-6-6
NO
all are 141 no
NO
all are 142 no
NO
all are 143 no
NO
all are 144 no
NO
all are 145 no
680--0-8-6
682--2-8-6
684--4-8-6
686--6-8-6
688--8-8-6
NO
all are 146 no
NO
all are 147 no
NO
all are 148 no
NO
all are 149 no
NO
all are 150 no
NO
all are 151 no
NO
all are 152 no
NO
all are 153 no
NO
all are 154 no
NO
all are 155 no
710--0-1-7
712--2-1-7
714--4-1-7
716--6-1-7
718--8-1-7
NO
all are 156 no
NO
all are 157 no
NO
all are 158 no
NO
all are 159 no
NO
all are 160 no
730--0-3-7
732--2-3-7
734--4-3-7
736--6-3-7
738--8-3-7
NO
all are 161 no
NO
all are 162 no
NO
all are 163 no
NO
all are 164 no
NO
all are 165 no
750--0-5-7
752--2-5-7
754--4-5-7
756--6-5-7
758--8-5-7
NO
all are 166 no
NO
all are 167 no
NO
all are 168 no
NO
all are 169 no
NO
all are 170 no
770--0-7-7
772--2-7-7
774--4-7-7
776--6-7-7
778--8-7-7
NO
all are 171 no
NO
all are 172 no
NO
all are 173 no
NO
all are 174 no
NO
all are 175 no
790--0-9-7
792--2-9-7
794--4-9-7
796--6-9-7
798--8-9-7
800--0-0-8
802--2-0-8
804--4-0-8
806--6-0-8
808--8-0-8
NO
all are 176 no
NO
all are 177 no
NO
all are 178 no
NO
all are 179 no
NO
all are 180 no
820--0-2-8
822--2-2-8
824--4-2-8
826--6-2-8
828--8-2-8
NO
all are 181 no
NO
all are 182 no
NO
all are 183 no
NO
all are 184 no
NO
all are 185 no
840--0-4-8
842--2-4-8
844--4-4-8
846--6-4-8
848--8-4-8
NO
all are 186 no
NO
all are 187 no
NO
all are 188 no
NO
all are 189 no
NO
all are 190 no
860--0-6-8
862--2-6-8
864--4-6-8
866--6-6-8
868--8-6-8
NO
all are 191 no
NO
all are 192 no
NO
all are 193 no
NO
all are 194 no
NO
all are 195 no
880--0-8-8
882--2-8-8
884--4-8-8
886--6-8-8
888--8-8-8
NO
all are 196 no
NO
all are 197 no
NO
all are 198 no
NO
all are 199 no
NO
all are 200 no
NO
all are 201 no
NO
all are 202 no
NO
all are 203 no
NO
all are 204 no
NO
all are 205 no
910--0-1-9
912--2-1-9
914--4-1-9
916--6-1-9
918--8-1-9
NO
all are 206 no
NO
all are 207 no
NO
all are 208 no
NO
all are 209 no
NO
all are 210 no
930--0-3-9
932--2-3-9
934--4-3-9
936--6-3-9
938--8-3-9
NO
all are 211 no
NO
all are 212 no
NO
all are 213 no
NO
all are 214 no
NO
all are 215 no
950--0-5-9
952--2-5-9
954--4-5-9
956--6-5-9
958--8-5-9
NO
all are 216 no
NO
all are 217 no
NO
all are 218 no
NO
all are 219 no
NO
all are 220 no
970--0-7-9
972--2-7-9
974--4-7-9
976--6-7-9
978--8-7-9
NO
all are 221 no
NO
all are 222 no
NO
all are 223 no
NO
all are 224 no
NO
all are 225 no
990--0-9-9
992--2-9-9
994--4-9-9
996--6-9-9
998--8-9-9

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不一定是2的倍数。例如：102/2=51 （1+2）/2=3/2 也就是说，当三位数中十位或百位出现奇数时，有可能三个数字之和不一定是2的倍数。