Cuantos múltiplos de 3 cifras son múltiplos de 3 pero no de 9?

Tendremos que encontrar los múltiplos de "3" de 3 cifras para saber cuáles son múltiplos de 3 que no sean de "9".

3 x 1 = 3

3 x 2 = 6

3 x 3 = 9

3 x 4 = 12

3 x 5 = 15

3 x 6 = 18

3 x 7 = 21

3 x 8 = 24

3 x 9 = 27

3 x 10 = 30

3 x 11 = 33

3 x 12 = 36

3 x 13 = 39

3 x 14 = 42

3 x 15 = 45

3 x 16 = 48

3 x 17 = 51

3 x 18 = 54

3 x 19 = 57

3 x 20 = 60

3 x 21 = 63

3 x 22 = 66

3 x 23 = 69

3 x 24 = 72

3 x 25 = 75

3 x 26 = 78

3 x 27 = 81

3 x 28 = 84

3 x 29 = 87

3 x 30 = 90

3 x 31 = 93

3 x 32 = 96

3 x 33 = 99

3 x 34 = 102

3 x 35 = 105

3 x 36 = 108

3 x 37 = 111

3 x 38 = 114

3 x 39 = 117

3 x 40 = 120

3 x 41 = 123

3 x 42 = 126

3 x 43 = 129

3 x 44 = 132

3 x 45 = 135

3 x 46 = 138

3 x 47 = 141

3 x 48 = 144

3 x 49 = 147

3 x 50 = 150

3 x 51 = 153

3 x 52 = 156

3 x 53 = 159

3 x 54 = 162

3 x 55 = 165

3 x 56 = 168

3 x 57 = 171

3 x 58 = 174

3 x 59 = 177

3 x 60 = 180

3 x 61 = 183

3 x 62 = 186

3 x 63 = 189

3 x 64 = 192

3 x 65 = 195

3 x 66 = 198

3 x 67 = 201

3 x 68 = 204

3 x 69 = 207

3 x 70 = 210

3 x 71 = 213

3 x 72 = 216

3 x 73 = 219

3 x 74 = 222

3 x 75 = 225

3 x 76 = 228

3 x 77 = 231

3 x 78 = 234

3 x 79 = 237

3 x 80 = 240

3 x 81 = 243

3 x 82 = 246

3 x 83 = 249

3 x 84 = 252

3 x 85 = 255

3 x 86 = 258

3 x 87 = 261

3 x 88 = 264

3 x 89 = 267

3 x 90 = 270

3 x 91 = 273

3 x 92 = 276

3 x 93 = 279

3 x 94 = 282

3 x 95 = 285

3 x 96 = 288

3 x 97 = 291

3 x 98 = 294

3 x 99 = 297

3 x 100 = 300

3 x 101 = 303

3 x 102 = 306

3 x 103 = 309

3 x 104 = 312

3 x 105 = 315

3 x 106 = 318

3 x 107 = 321

3 x 108 = 324

3 x 109 = 327

3 x 110 = 330

3 x 111 = 333

3 x 112 = 336

3 x 113 = 339

3 x 114 = 342

3 x 115 = 345

3 x 116 = 348

3 x 117 = 351

3 x 118 = 354

3 x 119 = 357

3 x 120 = 360

3 x 121 = 363

3 x 122 = 366

3 x 123 = 369

3 x 124 = 372

3 x 125 = 375

3 x 126 = 378

3 x 127 = 381

3 x 128 = 384

3 x 129 = 387

3 x 130 = 390

3 x 131 = 393

3 x 132 = 396

3 x 133 = 399

3 x 134 = 402

3 x 135 = 405

3 x 136 = 408

3 x 137 = 411

3 x 138 = 414

3 x 139 = 417

3 x 140 = 420

3 x 141 = 423

3 x 142 = 426

3 x 143 = 429

3 x 144 = 432

3 x 145 = 435

3 x 146 = 438

3 x 147 = 441

3 x 148 = 444

3 x 149 = 447

3 x 150 = 450

3 x 151 = 453

3 x 152 = 456

3 x 153 = 459

3 x 154 = 462

3 x 155 = 465

3 x 156 = 468

3 x 157 = 471

3 x 158 = 474

3 x 159 = 477

3 x 160 = 480

3 x 161 = 483

3 x 162 = 486

3 x 163 = 489

3 x 164 = 492

3 x 165 = 495

3 x 166 = 498

3 x 167 = 501

3 x 168 = 504

3 x 169 = 507

3 x 170 = 510

3 x 171 = 513

3 x 172 = 516

3 x 173 = 519

3 x 174 = 522

3 x 175 = 525

3 x 176 = 528

3 x 177 = 531

3 x 178 = 534

3 x 179 = 537

3 x 180 = 540

3 x 181 = 543

3 x 182 = 546

3 x 183 = 549

3 x 184 = 552

3 x 185 = 555

3 x 186 = 558

3 x 187 = 561

3 x 188 = 564

3 x 189 = 567

3 x 190 = 570

3 x 191 = 573

3 x 192 = 576

3 x 193 = 579

3 x 194 = 582

3 x 195 = 585

3 x 196 = 588

3 x 197 = 591

3 x 198 = 594

3 x 199 = 597

3 x 200 = 600

3 x 201 = 603

3 x 202 = 606

3 x 203 = 609

3 x 204 = 612

3 x 205 = 615

3 x 206 = 618

3 x 207 = 621

3 x 208 = 624

3 x 209 = 627

3 x 210 = 630

3 x 211 = 633

3 x 212 = 636

3 x 213 = 639

3 x 214 = 642

3 x 215 = 645

3 x 216 = 648

3 x 217 = 651

3 x 218 = 654

3 x 219 = 657

3 x 220 = 660

3 x 221 = 663

3 x 222 = 666

3 x 223 = 669

3 x 224 = 672

3 x 225 = 675

3 x 226 = 678

3 x 227 = 681

3 x 228 = 684

3 x 229 = 687

3 x 230 = 690

3 x 231 = 693

3 x 232 = 696

3 x 233 = 699

3 x 234 = 702

3 x 235 = 705

3 x 236 = 708

3 x 238 = 712

3 x 239 = 715

3 x 240 = 718.

Los múltiplos de 9 a partir de 100 : 108, 117, 126, 135, 144, 153, 162, 171, 180, 189, 198, 207, 216, 225, 234, 243, 252, 261, 270, 279, 288, 297, 306, 315, 324, 333, 342, 351, 360, 369, 378, 387, 396, 405, 414, 423, 432, 441, 450, 459, 468, 477, 486, 495, 504, 513, 522, 531, 540, 549, 558, 567, 576, 585, 594, 603, 612, 621, 630, 639, 648, 657, 666, 675, 684, 693, 702, 711, 720 729, 738, 747, 756, 765, 774, 783, 792, 801, 810, 819, 828 837, 846, 855, 864, 873, 882, 891, 900, 909, 918, 927, 936 945, 954, 963, 972, 981, 990, 999, 1008.

Los múltiplos de "3" de tres cifras que no son de "9" son :

102, 105, 111, 114, 120, 123, 129, 132, 138, 141, 147, 150, 156, 159, 165, 169, 174, 177, 183, 186, 192, 195, 201, 204, 210, 213, 219, 222, 228, 231, 237, 240, 246, 249, 255, 258, 264, 267, 273, 276, 282, 285, 291, 294, 300, 303, 309, 312, 318, 321, 327, 330, 336, 339, 345, 348, 354, 357, 363, 366, 372, 375.

Para saber exactamente cuántos múltiplos hay de tres cifras de 3 pero no de 9, debemos de empezar desde 100 hasta 999,

999 + 1 - 100 = 900.