Let's roll up our sleeves and solve this. We have 420 and we're going to multiply it by 492, essentially adding 420 to itself 492 times.
Step 1: 0 + 420 = 420
Step 2: 420 + 420 = 840
Step 3: 840 + 420 = 1260
Step 4: 1260 + 420 = 1680
Step 5: 1680 + 420 = 2100
Step 6: 2100 + 420 = 2520
Step 7: 2520 + 420 = 2940
Step 8: 2940 + 420 = 3360
Step 9: 3360 + 420 = 3780
Step 10: 3780 + 420 = 4200
Step 11: 4200 + 420 = 4620
Step 12: 4620 + 420 = 5040
Step 13: 5040 + 420 = 5460
Step 14: 5460 + 420 = 5880
Step 15: 5880 + 420 = 6300
Step 16: 6300 + 420 = 6720
Step 17: 6720 + 420 = 7140
Step 18: 7140 + 420 = 7560
Step 19: 7560 + 420 = 7980
Step 20: 7980 + 420 = 8400
Step 21: 8400 + 420 = 8820
Step 22: 8820 + 420 = 9240
Step 23: 9240 + 420 = 9660
Step 24: 9660 + 420 = 10080
Step 25: 10080 + 420 = 10500
Step 26: 10500 + 420 = 10920
Step 27: 10920 + 420 = 11340
Step 28: 11340 + 420 = 11760
Step 29: 11760 + 420 = 12180
Step 30: 12180 + 420 = 12600
Step 31: 12600 + 420 = 13020
Step 32: 13020 + 420 = 13440
Step 33: 13440 + 420 = 13860
Step 34: 13860 + 420 = 14280
Step 35: 14280 + 420 = 14700
Step 36: 14700 + 420 = 15120
Step 37: 15120 + 420 = 15540
Step 38: 15540 + 420 = 15960
Step 39: 15960 + 420 = 16380
Step 40: 16380 + 420 = 16800
Step 41: 16800 + 420 = 17220
Step 42: 17220 + 420 = 17640
Step 43: 17640 + 420 = 18060
Step 44: 18060 + 420 = 18480
Step 45: 18480 + 420 = 18900
Step 46: 18900 + 420 = 19320
Step 47: 19320 + 420 = 19740
Step 48: 19740 + 420 = 20160
Step 49: 20160 + 420 = 20580
Step 50: 20580 + 420 = 21000
Step 51: 21000 + 420 = 21420
Step 52: 21420 + 420 = 21840
Step 53: 21840 + 420 = 22260
Step 54: 22260 + 420 = 22680
Step 55: 22680 + 420 = 23100
Step 56: 23100 + 420 = 23520
Step 57: 23520 + 420 = 23940
Step 58: 23940 + 420 = 24360
Step 59: 24360 + 420 = 24780
Step 60: 24780 + 420 = 25200
Step 61: 25200 + 420 = 25620
Step 62: 25620 + 420 = 26040
Step 63: 26040 + 420 = 26460
Step 64: 26460 + 420 = 26880
Step 65: 26880 + 420 = 27300
Step 66: 27300 + 420 = 27720
Step 67: 27720 + 420 = 28140
Step 68: 28140 + 420 = 28560
Step 69: 28560 + 420 = 28980
Step 70: 28980 + 420 = 29400
Step 71: 29400 + 420 = 29820
Step 72: 29820 + 420 = 30240
Step 73: 30240 + 420 = 30660
Step 74: 30660 + 420 = 31080
Step 75: 31080 + 420 = 31500
Step 76: 31500 + 420 = 31920
Step 77: 31920 + 420 = 32340
Step 78: 32340 + 420 = 32760
Step 79: 32760 + 420 = 33180
Step 80: 33180 + 420 = 33600
Step 81: 33600 + 420 = 34020
Step 82: 34020 + 420 = 34440
Step 83: 34440 + 420 = 34860
Step 84: 34860 + 420 = 35280
Step 85: 35280 + 420 = 35700
Step 86: 35700 + 420 = 36120
Step 87: 36120 + 420 = 36540
Step 88: 36540 + 420 = 36960
Step 89: 36960 + 420 = 37380
Step 90: 37380 + 420 = 37800
Step 91: 37800 + 420 = 38220
Step 92: 38220 + 420 = 38640
Step 93: 38640 + 420 = 39060
Step 94: 39060 + 420 = 39480
Step 95: 39480 + 420 = 39900
Step 96: 39900 + 420 = 40320
Step 97: 40320 + 420 = 40740
Step 98: 40740 + 420 = 41160
Step 99: 41160 + 420 = 41580
Step 100: 41580 + 420 = 42000
Step 101: 42000 + 420 = 42420
Step 102: 42420 + 420 = 42840
Step 103: 42840 + 420 = 43260
Step 104: 43260 + 420 = 43680
Step 105: 43680 + 420 = 44100
Step 106: 44100 + 420 = 44520
Step 107: 44520 + 420 = 44940
Step 108: 44940 + 420 = 45360
Step 109: 45360 + 420 = 45780
Step 110: 45780 + 420 = 46200
Step 111: 46200 + 420 = 46620
Step 112: 46620 + 420 = 47040
Step 113: 47040 + 420 = 47460
Step 114: 47460 + 420 = 47880
Step 115: 47880 + 420 = 48300
Step 116: 48300 + 420 = 48720
Step 117: 48720 + 420 = 49140
Step 118: 49140 + 420 = 49560
Step 119: 49560 + 420 = 49980
Step 120: 49980 + 420 = 50400
Step 121: 50400 + 420 = 50820
Step 122: 50820 + 420 = 51240
Step 123: 51240 + 420 = 51660
Step 124: 51660 + 420 = 52080
Step 125: 52080 + 420 = 52500
Step 126: 52500 + 420 = 52920
Step 127: 52920 + 420 = 53340
Step 128: 53340 + 420 = 53760
Step 129: 53760 + 420 = 54180
Step 130: 54180 + 420 = 54600
Step 131: 54600 + 420 = 55020
Step 132: 55020 + 420 = 55440
Step 133: 55440 + 420 = 55860
Step 134: 55860 + 420 = 56280
Step 135: 56280 + 420 = 56700
Step 136: 56700 + 420 = 57120
Step 137: 57120 + 420 = 57540
Step 138: 57540 + 420 = 57960
Step 139: 57960 + 420 = 58380
Step 140: 58380 + 420 = 58800
Step 141: 58800 + 420 = 59220
Step 142: 59220 + 420 = 59640
Step 143: 59640 + 420 = 60060
Step 144: 60060 + 420 = 60480
Step 145: 60480 + 420 = 60900
Step 146: 60900 + 420 = 61320
Step 147: 61320 + 420 = 61740
Step 148: 61740 + 420 = 62160
Step 149: 62160 + 420 = 62580
Step 150: 62580 + 420 = 63000
Step 151: 63000 + 420 = 63420
Step 152: 63420 + 420 = 63840
Step 153: 63840 + 420 = 64260
Step 154: 64260 + 420 = 64680
Step 155: 64680 + 420 = 65100
Step 156: 65100 + 420 = 65520
Step 157: 65520 + 420 = 65940
Step 158: 65940 + 420 = 66360
Step 159: 66360 + 420 = 66780
Step 160: 66780 + 420 = 67200
Step 161: 67200 + 420 = 67620
Step 162: 67620 + 420 = 68040
Step 163: 68040 + 420 = 68460
Step 164: 68460 + 420 = 68880
Step 165: 68880 + 420 = 69300
Step 166: 69300 + 420 = 69720
Step 167: 69720 + 420 = 70140
Step 168: 70140 + 420 = 70560
Step 169: 70560 + 420 = 70980
Step 170: 70980 + 420 = 71400
Step 171: 71400 + 420 = 71820
Step 172: 71820 + 420 = 72240
Step 173: 72240 + 420 = 72660
Step 174: 72660 + 420 = 73080
Step 175: 73080 + 420 = 73500
Step 176: 73500 + 420 = 73920
Step 177: 73920 + 420 = 74340
Step 178: 74340 + 420 = 74760
Step 179: 74760 + 420 = 75180
Step 180: 75180 + 420 = 75600
Step 181: 75600 + 420 = 76020
Step 182: 76020 + 420 = 76440
Step 183: 76440 + 420 = 76860
Step 184: 76860 + 420 = 77280
Step 185: 77280 + 420 = 77700
Step 186: 77700 + 420 = 78120
Step 187: 78120 + 420 = 78540
Step 188: 78540 + 420 = 78960
Step 189: 78960 + 420 = 79380
Step 190: 79380 + 420 = 79800
Step 191: 79800 + 420 = 80220
Step 192: 80220 + 420 = 80640
Step 193: 80640 + 420 = 81060
Step 194: 81060 + 420 = 81480
Step 195: 81480 + 420 = 81900
Step 196: 81900 + 420 = 82320
Step 197: 82320 + 420 = 82740
Step 198: 82740 + 420 = 83160
Step 199: 83160 + 420 = 83580
Step 200: 83580 + 420 = 84000
Step 201: 84000 + 420 = 84420
Step 202: 84420 + 420 = 84840
Step 203: 84840 + 420 = 85260
Step 204: 85260 + 420 = 85680
Step 205: 85680 + 420 = 86100
Step 206: 86100 + 420 = 86520
Step 207: 86520 + 420 = 86940
Step 208: 86940 + 420 = 87360
Step 209: 87360 + 420 = 87780
Step 210: 87780 + 420 = 88200
Step 211: 88200 + 420 = 88620
Step 212: 88620 + 420 = 89040
Step 213: 89040 + 420 = 89460
Step 214: 89460 + 420 = 89880
Step 215: 89880 + 420 = 90300
Step 216: 90300 + 420 = 90720
Step 217: 90720 + 420 = 91140
Step 218: 91140 + 420 = 91560
Step 219: 91560 + 420 = 91980
Step 220: 91980 + 420 = 92400
Step 221: 92400 + 420 = 92820
Step 222: 92820 + 420 = 93240
Step 223: 93240 + 420 = 93660
Step 224: 93660 + 420 = 94080
Step 225: 94080 + 420 = 94500
Step 226: 94500 + 420 = 94920
Step 227: 94920 + 420 = 95340
Step 228: 95340 + 420 = 95760
Step 229: 95760 + 420 = 96180
Step 230: 96180 + 420 = 96600
Step 231: 96600 + 420 = 97020
Step 232: 97020 + 420 = 97440
Step 233: 97440 + 420 = 97860
Step 234: 97860 + 420 = 98280
Step 235: 98280 + 420 = 98700
Step 236: 98700 + 420 = 99120
Step 237: 99120 + 420 = 99540
Step 238: 99540 + 420 = 99960
Step 239: 99960 + 420 = 100380
Step 240: 100380 + 420 = 100800
Step 241: 100800 + 420 = 101220
Step 242: 101220 + 420 = 101640
Step 243: 101640 + 420 = 102060
Step 244: 102060 + 420 = 102480
Step 245: 102480 + 420 = 102900
Step 246: 102900 + 420 = 103320
Step 247: 103320 + 420 = 103740
Step 248: 103740 + 420 = 104160
Step 249: 104160 + 420 = 104580
Step 250: 104580 + 420 = 105000
Step 251: 105000 + 420 = 105420
Step 252: 105420 + 420 = 105840
Step 253: 105840 + 420 = 106260
Step 254: 106260 + 420 = 106680
Step 255: 106680 + 420 = 107100
Step 256: 107100 + 420 = 107520
Step 257: 107520 + 420 = 107940
Step 258: 107940 + 420 = 108360
Step 259: 108360 + 420 = 108780
Step 260: 108780 + 420 = 109200
Step 261: 109200 + 420 = 109620
Step 262: 109620 + 420 = 110040
Step 263: 110040 + 420 = 110460
Step 264: 110460 + 420 = 110880
Step 265: 110880 + 420 = 111300
Step 266: 111300 + 420 = 111720
Step 267: 111720 + 420 = 112140
Step 268: 112140 + 420 = 112560
Step 269: 112560 + 420 = 112980
Step 270: 112980 + 420 = 113400
Step 271: 113400 + 420 = 113820
Step 272: 113820 + 420 = 114240
Step 273: 114240 + 420 = 114660
Step 274: 114660 + 420 = 115080
Step 275: 115080 + 420 = 115500
Step 276: 115500 + 420 = 115920
Step 277: 115920 + 420 = 116340
Step 278: 116340 + 420 = 116760
Step 279: 116760 + 420 = 117180
Step 280: 117180 + 420 = 117600
Step 281: 117600 + 420 = 118020
Step 282: 118020 + 420 = 118440
Step 283: 118440 + 420 = 118860
Step 284: 118860 + 420 = 119280
Step 285: 119280 + 420 = 119700
Step 286: 119700 + 420 = 120120
Step 287: 120120 + 420 = 120540
Step 288: 120540 + 420 = 120960
Step 289: 120960 + 420 = 121380
Step 290: 121380 + 420 = 121800
Step 291: 121800 + 420 = 122220
Step 292: 122220 + 420 = 122640
Step 293: 122640 + 420 = 123060
Step 294: 123060 + 420 = 123480
Step 295: 123480 + 420 = 123900
Step 296: 123900 + 420 = 124320
Step 297: 124320 + 420 = 124740
Step 298: 124740 + 420 = 125160
Step 299: 125160 + 420 = 125580
Step 300: 125580 + 420 = 126000
Step 301: 126000 + 420 = 126420
Step 302: 126420 + 420 = 126840
Step 303: 126840 + 420 = 127260
Step 304: 127260 + 420 = 127680
Step 305: 127680 + 420 = 128100
Step 306: 128100 + 420 = 128520
Step 307: 128520 + 420 = 128940
Step 308: 128940 + 420 = 129360
Step 309: 129360 + 420 = 129780
Step 310: 129780 + 420 = 130200
Step 311: 130200 + 420 = 130620
Step 312: 130620 + 420 = 131040
Step 313: 131040 + 420 = 131460
Step 314: 131460 + 420 = 131880
Step 315: 131880 + 420 = 132300
Step 316: 132300 + 420 = 132720
Step 317: 132720 + 420 = 133140
Step 318: 133140 + 420 = 133560
Step 319: 133560 + 420 = 133980
Step 320: 133980 + 420 = 134400
Step 321: 134400 + 420 = 134820
Step 322: 134820 + 420 = 135240
Step 323: 135240 + 420 = 135660
Step 324: 135660 + 420 = 136080
Step 325: 136080 + 420 = 136500
Step 326: 136500 + 420 = 136920
Step 327: 136920 + 420 = 137340
Step 328: 137340 + 420 = 137760
Step 329: 137760 + 420 = 138180
Step 330: 138180 + 420 = 138600
Step 331: 138600 + 420 = 139020
Step 332: 139020 + 420 = 139440
Step 333: 139440 + 420 = 139860
Step 334: 139860 + 420 = 140280
Step 335: 140280 + 420 = 140700
Step 336: 140700 + 420 = 141120
Step 337: 141120 + 420 = 141540
Step 338: 141540 + 420 = 141960
Step 339: 141960 + 420 = 142380
Step 340: 142380 + 420 = 142800
Step 341: 142800 + 420 = 143220
Step 342: 143220 + 420 = 143640
Step 343: 143640 + 420 = 144060
Step 344: 144060 + 420 = 144480
Step 345: 144480 + 420 = 144900
Step 346: 144900 + 420 = 145320
Step 347: 145320 + 420 = 145740
Step 348: 145740 + 420 = 146160
Step 349: 146160 + 420 = 146580
Step 350: 146580 + 420 = 147000
Step 351: 147000 + 420 = 147420
Step 352: 147420 + 420 = 147840
Step 353: 147840 + 420 = 148260
Step 354: 148260 + 420 = 148680
Step 355: 148680 + 420 = 149100
Step 356: 149100 + 420 = 149520
Step 357: 149520 + 420 = 149940
Step 358: 149940 + 420 = 150360
Step 359: 150360 + 420 = 150780
Step 360: 150780 + 420 = 151200
Step 361: 151200 + 420 = 151620
Step 362: 151620 + 420 = 152040
Step 363: 152040 + 420 = 152460
Step 364: 152460 + 420 = 152880
Step 365: 152880 + 420 = 153300
Step 366: 153300 + 420 = 153720
Step 367: 153720 + 420 = 154140
Step 368: 154140 + 420 = 154560
Step 369: 154560 + 420 = 154980
Step 370: 154980 + 420 = 155400
Step 371: 155400 + 420 = 155820
Step 372: 155820 + 420 = 156240
Step 373: 156240 + 420 = 156660
Step 374: 156660 + 420 = 157080
Step 375: 157080 + 420 = 157500
Step 376: 157500 + 420 = 157920
Step 377: 157920 + 420 = 158340
Step 378: 158340 + 420 = 158760
Step 379: 158760 + 420 = 159180
Step 380: 159180 + 420 = 159600
Step 381: 159600 + 420 = 160020
Step 382: 160020 + 420 = 160440
Step 383: 160440 + 420 = 160860
Step 384: 160860 + 420 = 161280
Step 385: 161280 + 420 = 161700
Step 386: 161700 + 420 = 162120
Step 387: 162120 + 420 = 162540
Step 388: 162540 + 420 = 162960
Step 389: 162960 + 420 = 163380
Step 390: 163380 + 420 = 163800
Step 391: 163800 + 420 = 164220
Step 392: 164220 + 420 = 164640
Step 393: 164640 + 420 = 165060
Step 394: 165060 + 420 = 165480
Step 395: 165480 + 420 = 165900
Step 396: 165900 + 420 = 166320
Step 397: 166320 + 420 = 166740
Step 398: 166740 + 420 = 167160
Step 399: 167160 + 420 = 167580
Step 400: 167580 + 420 = 168000
Step 401: 168000 + 420 = 168420
Step 402: 168420 + 420 = 168840
Step 403: 168840 + 420 = 169260
Step 404: 169260 + 420 = 169680
Step 405: 169680 + 420 = 170100
Step 406: 170100 + 420 = 170520
Step 407: 170520 + 420 = 170940
Step 408: 170940 + 420 = 171360
Step 409: 171360 + 420 = 171780
Step 410: 171780 + 420 = 172200
Step 411: 172200 + 420 = 172620
Step 412: 172620 + 420 = 173040
Step 413: 173040 + 420 = 173460
Step 414: 173460 + 420 = 173880
Step 415: 173880 + 420 = 174300
Step 416: 174300 + 420 = 174720
Step 417: 174720 + 420 = 175140
Step 418: 175140 + 420 = 175560
Step 419: 175560 + 420 = 175980
Step 420: 175980 + 420 = 176400
Step 421: 176400 + 420 = 176820
Step 422: 176820 + 420 = 177240
Step 423: 177240 + 420 = 177660
Step 424: 177660 + 420 = 178080
Step 425: 178080 + 420 = 178500
Step 426: 178500 + 420 = 178920
Step 427: 178920 + 420 = 179340
Step 428: 179340 + 420 = 179760
Step 429: 179760 + 420 = 180180
Step 430: 180180 + 420 = 180600
Step 431: 180600 + 420 = 181020
Step 432: 181020 + 420 = 181440
Step 433: 181440 + 420 = 181860
Step 434: 181860 + 420 = 182280
Step 435: 182280 + 420 = 182700
Step 436: 182700 + 420 = 183120
Step 437: 183120 + 420 = 183540
Step 438: 183540 + 420 = 183960
Step 439: 183960 + 420 = 184380
Step 440: 184380 + 420 = 184800
Step 441: 184800 + 420 = 185220
Step 442: 185220 + 420 = 185640
Step 443: 185640 + 420 = 186060
Step 444: 186060 + 420 = 186480
Step 445: 186480 + 420 = 186900
Step 446: 186900 + 420 = 187320
Step 447: 187320 + 420 = 187740
Step 448: 187740 + 420 = 188160
Step 449: 188160 + 420 = 188580
Step 450: 188580 + 420 = 189000
Step 451: 189000 + 420 = 189420
Step 452: 189420 + 420 = 189840
Step 453: 189840 + 420 = 190260
Step 454: 190260 + 420 = 190680
Step 455: 190680 + 420 = 191100
Step 456: 191100 + 420 = 191520
Step 457: 191520 + 420 = 191940
Step 458: 191940 + 420 = 192360
Step 459: 192360 + 420 = 192780
Step 460: 192780 + 420 = 193200
Step 461: 193200 + 420 = 193620
Step 462: 193620 + 420 = 194040
Step 463: 194040 + 420 = 194460
Step 464: 194460 + 420 = 194880
Step 465: 194880 + 420 = 195300
Step 466: 195300 + 420 = 195720
Step 467: 195720 + 420 = 196140
Step 468: 196140 + 420 = 196560
Step 469: 196560 + 420 = 196980
Step 470: 196980 + 420 = 197400
Step 471: 197400 + 420 = 197820
Step 472: 197820 + 420 = 198240
Step 473: 198240 + 420 = 198660
Step 474: 198660 + 420 = 199080
Step 475: 199080 + 420 = 199500
Step 476: 199500 + 420 = 199920
Step 477: 199920 + 420 = 200340
Step 478: 200340 + 420 = 200760
Step 479: 200760 + 420 = 201180
Step 480: 201180 + 420 = 201600
Step 481: 201600 + 420 = 202020
Step 482: 202020 + 420 = 202440
Step 483: 202440 + 420 = 202860
Step 484: 202860 + 420 = 203280
Step 485: 203280 + 420 = 203700
Step 486: 203700 + 420 = 204120
Step 487: 204120 + 420 = 204540
Step 488: 204540 + 420 = 204960
Step 489: 204960 + 420 = 205380
Step 490: 205380 + 420 = 205800
Step 491: 205800 + 420 = 206220
Step 492: 206220 + 420 = 206640

So, 420*492 = 206640