LCM for 320 and 640

The first method to find LCM for numbers 320 and 640 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 320 and 640 is 320, so

LCM = (320 × 640) ÷ 320

LCM = 204800 ÷ 320

LCM = 640

The second method to find LCM for numbers 320 and 640 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 320: 320, 640, 960, 1280

Multiples of 640: 640, 1280, 1920, 2560, 3200, 3840, 4480, 5120, 5760, 6400, 7040, 7680, 8320, 8960, 9600, 10240, 10880, 11520, 12160, 12800, 13440, 14080, 14720, 15360, 16000, 16640, 17280, 17920, 18560, 19200, 19840, 20480, 21120, 21760, 22400, 23040, 23680, 24320, 24960, 25600, 26240, 26880, 27520, 28160, 28800, 29440, 30080, 30720, 31360, 32000, 32640, 33280, 33920, 34560, 35200, 35840, 36480, 37120, 37760, 38400, 39040, 39680, 40320, 40960, 41600, 42240, 42880, 43520, 44160, 44800, 45440, 46080, 46720, 47360, 48000, 48640, 49280, 49920, 50560, 51200, 51840, 52480, 53120, 53760, 54400, 55040, 55680, 56320, 56960, 57600, 58240, 58880, 59520, 60160, 60800, 61440, 62080, 62720, 63360, 64000, 64640, 65280, 65920, 66560, 67200, 67840, 68480, 69120, 69760, 70400, 71040, 71680, 72320, 72960, 73600, 74240, 74880, 75520, 76160, 76800, 77440, 78080, 78720, 79360, 80000, 80640, 81280, 81920, 82560, 83200, 83840, 84480, 85120, 85760, 86400, 87040, 87680, 88320, 88960, 89600, 90240, 90880, 91520, 92160, 92800, 93440, 94080, 94720, 95360, 96000, 96640, 97280, 97920, 98560, 99200, 99840, 100480, 101120, 101760, 102400, 103040, 103680, 104320, 104960, 105600, 106240, 106880, 107520, 108160, 108800, 109440, 110080, 110720, 111360, 112000, 112640, 113280, 113920, 114560, 115200, 115840, 116480, 117120, 117760, 118400, 119040, 119680, 120320, 120960, 121600, 122240, 122880, 123520, 124160, 124800, 125440, 126080, 126720, 127360, 128000, 128640, 129280, 129920, 130560, 131200, 131840, 132480, 133120, 133760, 134400, 135040, 135680, 136320, 136960, 137600, 138240, 138880, 139520, 140160, 140800, 141440, 142080, 142720, 143360, 144000, 144640, 145280, 145920, 146560, 147200, 147840, 148480, 149120, 149760, 150400, 151040, 151680, 152320, 152960, 153600, 154240, 154880, 155520, 156160, 156800, 157440, 158080, 158720, 159360, 160000, 160640, 161280, 161920, 162560, 163200, 163840, 164480, 165120, 165760, 166400, 167040, 167680, 168320, 168960, 169600, 170240, 170880, 171520, 172160, 172800, 173440, 174080, 174720, 175360, 176000, 176640, 177280, 177920, 178560, 179200, 179840, 180480, 181120, 181760, 182400, 183040, 183680, 184320, 184960, 185600, 186240, 186880, 187520, 188160, 188800, 189440, 190080, 190720, 191360, 192000, 192640, 193280, 193920, 194560, 195200, 195840, 196480, 197120, 197760, 198400, 199040, 199680, 200320, 200960, 201600, 202240, 202880, 203520, 204160, 204800, 205440, 206080, 206720, 207360, 208000, 208640, 209280, 209920, 210560, 211200, 211840, 212480, 213120, 213760, 214400, 215040, 215680, 216320, 216960, 217600, 218240, 218880, 219520, 220160, 220800, 221440, 222080, 222720, 223360, 224000, 224640, 225280, 225920, 226560, 227200, 227840, 228480, 229120, 229760, 230400, 231040, 231680, 232320, 232960, 233600, 234240, 234880, 235520, 236160, 236800, 237440, 238080, 238720, 239360, 240000, 240640, 241280, 241920, 242560, 243200, 243840, 244480, 245120, 245760, 246400, 247040, 247680, 248320, 248960, 249600, 250240, 250880, 251520, 252160, 252800, 253440, 254080, 254720, 255360, 256000, 256640, 257280, 257920, 258560, 259200, 259840, 260480, 261120, 261760, 262400, 263040, 263680, 264320, 264960, 265600, 266240, 266880, 267520, 268160, 268800, 269440, 270080, 270720, 271360, 272000, 272640, 273280, 273920, 274560, 275200, 275840, 276480, 277120, 277760, 278400, 279040, 279680, 280320, 280960, 281600, 282240, 282880, 283520, 284160, 284800, 285440, 286080, 286720, 287360, 288000, 288640, 289280, 289920, 290560, 291200, 291840, 292480, 293120, 293760, 294400, 295040, 295680, 296320, 296960, 297600, 298240, 298880, 299520, 300160, 300800, 301440, 302080, 302720, 303360, 304000, 304640, 305280, 305920, 306560, 307200, 307840, 308480, 309120, 309760, 310400, 311040, 311680, 312320, 312960, 313600, 314240, 314880, 315520, 316160, 316800, 317440, 318080, 318720, 319360, 320000, 320640, 321280, 321920, 322560, 323200, 323840, 324480, 325120, 325760, 326400, 327040, 327680, 328320, 328960, 329600, 330240, 330880, 331520, 332160, 332800, 333440, 334080, 334720, 335360, 336000, 336640, 337280, 337920, 338560, 339200, 339840, 340480, 341120, 341760, 342400, 343040, 343680, 344320, 344960, 345600, 346240, 346880, 347520, 348160, 348800, 349440, 350080, 350720, 351360, 352000, 352640, 353280, 353920, 354560, 355200, 355840, 356480, 357120, 357760, 358400, 359040, 359680, 360320, 360960, 361600, 362240, 362880, 363520, 364160, 364800, 365440, 366080, 366720, 367360, 368000, 368640, 369280, 369920, 370560, 371200, 371840, 372480, 373120, 373760, 374400, 375040, 375680, 376320, 376960, 377600, 378240, 378880, 379520, 380160, 380800, 381440, 382080, 382720, 383360, 384000, 384640, 385280, 385920, 386560, 387200, 387840, 388480, 389120, 389760, 390400, 391040, 391680, 392320, 392960, 393600, 394240, 394880, 395520, 396160, 396800, 397440, 398080, 398720, 399360, 400000, 400640, 401280, 401920, 402560, 403200, 403840, 404480, 405120, 405760, 406400, 407040, 407680, 408320, 408960, 409600, 410240, 410880, 411520, 412160, 412800, 413440, 414080, 414720, 415360, 416000, 416640, 417280, 417920, 418560, 419200, 419840, 420480, 421120, 421760, 422400, 423040, 423680, 424320, 424960, 425600, 426240, 426880, 427520, 428160, 428800, 429440, 430080, 430720, 431360, 432000, 432640, 433280, 433920, 434560, 435200, 435840, 436480, 437120, 437760, 438400, 439040, 439680, 440320, 440960, 441600, 442240, 442880, 443520, 444160, 444800, 445440, 446080, 446720, 447360, 448000, 448640, 449280, 449920, 450560, 451200, 451840, 452480, 453120, 453760, 454400, 455040, 455680, 456320, 456960, 457600, 458240, 458880, 459520, 460160, 460800, 461440, 462080, 462720, 463360, 464000, 464640, 465280, 465920, 466560, 467200, 467840, 468480, 469120, 469760, 470400, 471040, 471680, 472320, 472960, 473600, 474240, 474880, 475520, 476160, 476800, 477440, 478080, 478720, 479360, 480000, 480640, 481280, 481920, 482560, 483200, 483840, 484480, 485120, 485760, 486400, 487040, 487680, 488320, 488960, 489600, 490240, 490880, 491520, 492160, 492800, 493440, 494080, 494720, 495360, 496000, 496640, 497280, 497920, 498560, 499200, 499840, 500480, 501120, 501760, 502400, 503040, 503680, 504320, 504960, 505600, 506240, 506880, 507520, 508160, 508800, 509440, 510080, 510720, 511360, 512000, 512640, 513280, 513920, 514560, 515200, 515840, 516480, 517120, 517760, 518400, 519040, 519680, 520320, 520960, 521600, 522240, 522880, 523520, 524160, 524800, 525440, 526080, 526720, 527360, 528000, 528640, 529280, 529920, 530560, 531200, 531840, 532480, 533120, 533760, 534400, 535040, 535680, 536320, 536960, 537600, 538240, 538880, 539520, 540160, 540800, 541440, 542080, 542720, 543360, 544000, 544640, 545280, 545920, 546560, 547200, 547840, 548480, 549120, 549760, 550400, 551040, 551680, 552320, 552960, 553600, 554240, 554880, 555520, 556160, 556800, 557440, 558080, 558720, 559360, 560000, 560640, 561280, 561920, 562560, 563200, 563840, 564480, 565120, 565760, 566400, 567040, 567680, 568320, 568960, 569600, 570240, 570880, 571520, 572160, 572800, 573440, 574080, 574720, 575360, 576000, 576640, 577280, 577920, 578560, 579200, 579840, 580480, 581120, 581760, 582400, 583040, 583680, 584320, 584960, 585600, 586240, 586880, 587520, 588160, 588800, 589440, 590080, 590720, 591360, 592000, 592640, 593280, 593920, 594560, 595200, 595840, 596480, 597120, 597760, 598400, 599040, 599680, 600320, 600960, 601600, 602240, 602880, 603520, 604160, 604800, 605440, 606080, 606720, 607360, 608000, 608640, 609280, 609920, 610560, 611200, 611840, 612480, 613120, 613760, 614400, 615040, 615680, 616320, 616960, 617600, 618240, 618880, 619520, 620160, 620800, 621440, 622080, 622720, 623360, 624000, 624640, 625280, 625920, 626560, 627200, 627840, 628480, 629120, 629760, 630400, 631040, 631680, 632320, 632960, 633600, 634240, 634880, 635520, 636160, 636800, 637440, 638080, 638720, 639360, 640000, [...], 640

So the LCM for 320 and 640 is 640

Another method to find LCM for numbers 320 and 640 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors: