Let's get this math done. We have 372 and we're going to multiply it by 420. This is the same as taking 372 and adding it to itself 420 times.
Step 1: 0 + 372 = 372
Step 2: 372 + 372 = 744
Step 3: 744 + 372 = 1116
Step 4: 1116 + 372 = 1488
Step 5: 1488 + 372 = 1860
Step 6: 1860 + 372 = 2232
Step 7: 2232 + 372 = 2604
Step 8: 2604 + 372 = 2976
Step 9: 2976 + 372 = 3348
Step 10: 3348 + 372 = 3720
Step 11: 3720 + 372 = 4092
Step 12: 4092 + 372 = 4464
Step 13: 4464 + 372 = 4836
Step 14: 4836 + 372 = 5208
Step 15: 5208 + 372 = 5580
Step 16: 5580 + 372 = 5952
Step 17: 5952 + 372 = 6324
Step 18: 6324 + 372 = 6696
Step 19: 6696 + 372 = 7068
Step 20: 7068 + 372 = 7440
Step 21: 7440 + 372 = 7812
Step 22: 7812 + 372 = 8184
Step 23: 8184 + 372 = 8556
Step 24: 8556 + 372 = 8928
Step 25: 8928 + 372 = 9300
Step 26: 9300 + 372 = 9672
Step 27: 9672 + 372 = 10044
Step 28: 10044 + 372 = 10416
Step 29: 10416 + 372 = 10788
Step 30: 10788 + 372 = 11160
Step 31: 11160 + 372 = 11532
Step 32: 11532 + 372 = 11904
Step 33: 11904 + 372 = 12276
Step 34: 12276 + 372 = 12648
Step 35: 12648 + 372 = 13020
Step 36: 13020 + 372 = 13392
Step 37: 13392 + 372 = 13764
Step 38: 13764 + 372 = 14136
Step 39: 14136 + 372 = 14508
Step 40: 14508 + 372 = 14880
Step 41: 14880 + 372 = 15252
Step 42: 15252 + 372 = 15624
Step 43: 15624 + 372 = 15996
Step 44: 15996 + 372 = 16368
Step 45: 16368 + 372 = 16740
Step 46: 16740 + 372 = 17112
Step 47: 17112 + 372 = 17484
Step 48: 17484 + 372 = 17856
Step 49: 17856 + 372 = 18228
Step 50: 18228 + 372 = 18600
Step 51: 18600 + 372 = 18972
Step 52: 18972 + 372 = 19344
Step 53: 19344 + 372 = 19716
Step 54: 19716 + 372 = 20088
Step 55: 20088 + 372 = 20460
Step 56: 20460 + 372 = 20832
Step 57: 20832 + 372 = 21204
Step 58: 21204 + 372 = 21576
Step 59: 21576 + 372 = 21948
Step 60: 21948 + 372 = 22320
Step 61: 22320 + 372 = 22692
Step 62: 22692 + 372 = 23064
Step 63: 23064 + 372 = 23436
Step 64: 23436 + 372 = 23808
Step 65: 23808 + 372 = 24180
Step 66: 24180 + 372 = 24552
Step 67: 24552 + 372 = 24924
Step 68: 24924 + 372 = 25296
Step 69: 25296 + 372 = 25668
Step 70: 25668 + 372 = 26040
Step 71: 26040 + 372 = 26412
Step 72: 26412 + 372 = 26784
Step 73: 26784 + 372 = 27156
Step 74: 27156 + 372 = 27528
Step 75: 27528 + 372 = 27900
Step 76: 27900 + 372 = 28272
Step 77: 28272 + 372 = 28644
Step 78: 28644 + 372 = 29016
Step 79: 29016 + 372 = 29388
Step 80: 29388 + 372 = 29760
Step 81: 29760 + 372 = 30132
Step 82: 30132 + 372 = 30504
Step 83: 30504 + 372 = 30876
Step 84: 30876 + 372 = 31248
Step 85: 31248 + 372 = 31620
Step 86: 31620 + 372 = 31992
Step 87: 31992 + 372 = 32364
Step 88: 32364 + 372 = 32736
Step 89: 32736 + 372 = 33108
Step 90: 33108 + 372 = 33480
Step 91: 33480 + 372 = 33852
Step 92: 33852 + 372 = 34224
Step 93: 34224 + 372 = 34596
Step 94: 34596 + 372 = 34968
Step 95: 34968 + 372 = 35340
Step 96: 35340 + 372 = 35712
Step 97: 35712 + 372 = 36084
Step 98: 36084 + 372 = 36456
Step 99: 36456 + 372 = 36828
Step 100: 36828 + 372 = 37200
Step 101: 37200 + 372 = 37572
Step 102: 37572 + 372 = 37944
Step 103: 37944 + 372 = 38316
Step 104: 38316 + 372 = 38688
Step 105: 38688 + 372 = 39060
Step 106: 39060 + 372 = 39432
Step 107: 39432 + 372 = 39804
Step 108: 39804 + 372 = 40176
Step 109: 40176 + 372 = 40548
Step 110: 40548 + 372 = 40920
Step 111: 40920 + 372 = 41292
Step 112: 41292 + 372 = 41664
Step 113: 41664 + 372 = 42036
Step 114: 42036 + 372 = 42408
Step 115: 42408 + 372 = 42780
Step 116: 42780 + 372 = 43152
Step 117: 43152 + 372 = 43524
Step 118: 43524 + 372 = 43896
Step 119: 43896 + 372 = 44268
Step 120: 44268 + 372 = 44640
Step 121: 44640 + 372 = 45012
Step 122: 45012 + 372 = 45384
Step 123: 45384 + 372 = 45756
Step 124: 45756 + 372 = 46128
Step 125: 46128 + 372 = 46500
Step 126: 46500 + 372 = 46872
Step 127: 46872 + 372 = 47244
Step 128: 47244 + 372 = 47616
Step 129: 47616 + 372 = 47988
Step 130: 47988 + 372 = 48360
Step 131: 48360 + 372 = 48732
Step 132: 48732 + 372 = 49104
Step 133: 49104 + 372 = 49476
Step 134: 49476 + 372 = 49848
Step 135: 49848 + 372 = 50220
Step 136: 50220 + 372 = 50592
Step 137: 50592 + 372 = 50964
Step 138: 50964 + 372 = 51336
Step 139: 51336 + 372 = 51708
Step 140: 51708 + 372 = 52080
Step 141: 52080 + 372 = 52452
Step 142: 52452 + 372 = 52824
Step 143: 52824 + 372 = 53196
Step 144: 53196 + 372 = 53568
Step 145: 53568 + 372 = 53940
Step 146: 53940 + 372 = 54312
Step 147: 54312 + 372 = 54684
Step 148: 54684 + 372 = 55056
Step 149: 55056 + 372 = 55428
Step 150: 55428 + 372 = 55800
Step 151: 55800 + 372 = 56172
Step 152: 56172 + 372 = 56544
Step 153: 56544 + 372 = 56916
Step 154: 56916 + 372 = 57288
Step 155: 57288 + 372 = 57660
Step 156: 57660 + 372 = 58032
Step 157: 58032 + 372 = 58404
Step 158: 58404 + 372 = 58776
Step 159: 58776 + 372 = 59148
Step 160: 59148 + 372 = 59520
Step 161: 59520 + 372 = 59892
Step 162: 59892 + 372 = 60264
Step 163: 60264 + 372 = 60636
Step 164: 60636 + 372 = 61008
Step 165: 61008 + 372 = 61380
Step 166: 61380 + 372 = 61752
Step 167: 61752 + 372 = 62124
Step 168: 62124 + 372 = 62496
Step 169: 62496 + 372 = 62868
Step 170: 62868 + 372 = 63240
Step 171: 63240 + 372 = 63612
Step 172: 63612 + 372 = 63984
Step 173: 63984 + 372 = 64356
Step 174: 64356 + 372 = 64728
Step 175: 64728 + 372 = 65100
Step 176: 65100 + 372 = 65472
Step 177: 65472 + 372 = 65844
Step 178: 65844 + 372 = 66216
Step 179: 66216 + 372 = 66588
Step 180: 66588 + 372 = 66960
Step 181: 66960 + 372 = 67332
Step 182: 67332 + 372 = 67704
Step 183: 67704 + 372 = 68076
Step 184: 68076 + 372 = 68448
Step 185: 68448 + 372 = 68820
Step 186: 68820 + 372 = 69192
Step 187: 69192 + 372 = 69564
Step 188: 69564 + 372 = 69936
Step 189: 69936 + 372 = 70308
Step 190: 70308 + 372 = 70680
Step 191: 70680 + 372 = 71052
Step 192: 71052 + 372 = 71424
Step 193: 71424 + 372 = 71796
Step 194: 71796 + 372 = 72168
Step 195: 72168 + 372 = 72540
Step 196: 72540 + 372 = 72912
Step 197: 72912 + 372 = 73284
Step 198: 73284 + 372 = 73656
Step 199: 73656 + 372 = 74028
Step 200: 74028 + 372 = 74400
Step 201: 74400 + 372 = 74772
Step 202: 74772 + 372 = 75144
Step 203: 75144 + 372 = 75516
Step 204: 75516 + 372 = 75888
Step 205: 75888 + 372 = 76260
Step 206: 76260 + 372 = 76632
Step 207: 76632 + 372 = 77004
Step 208: 77004 + 372 = 77376
Step 209: 77376 + 372 = 77748
Step 210: 77748 + 372 = 78120
Step 211: 78120 + 372 = 78492
Step 212: 78492 + 372 = 78864
Step 213: 78864 + 372 = 79236
Step 214: 79236 + 372 = 79608
Step 215: 79608 + 372 = 79980
Step 216: 79980 + 372 = 80352
Step 217: 80352 + 372 = 80724
Step 218: 80724 + 372 = 81096
Step 219: 81096 + 372 = 81468
Step 220: 81468 + 372 = 81840
Step 221: 81840 + 372 = 82212
Step 222: 82212 + 372 = 82584
Step 223: 82584 + 372 = 82956
Step 224: 82956 + 372 = 83328
Step 225: 83328 + 372 = 83700
Step 226: 83700 + 372 = 84072
Step 227: 84072 + 372 = 84444
Step 228: 84444 + 372 = 84816
Step 229: 84816 + 372 = 85188
Step 230: 85188 + 372 = 85560
Step 231: 85560 + 372 = 85932
Step 232: 85932 + 372 = 86304
Step 233: 86304 + 372 = 86676
Step 234: 86676 + 372 = 87048
Step 235: 87048 + 372 = 87420
Step 236: 87420 + 372 = 87792
Step 237: 87792 + 372 = 88164
Step 238: 88164 + 372 = 88536
Step 239: 88536 + 372 = 88908
Step 240: 88908 + 372 = 89280
Step 241: 89280 + 372 = 89652
Step 242: 89652 + 372 = 90024
Step 243: 90024 + 372 = 90396
Step 244: 90396 + 372 = 90768
Step 245: 90768 + 372 = 91140
Step 246: 91140 + 372 = 91512
Step 247: 91512 + 372 = 91884
Step 248: 91884 + 372 = 92256
Step 249: 92256 + 372 = 92628
Step 250: 92628 + 372 = 93000
Step 251: 93000 + 372 = 93372
Step 252: 93372 + 372 = 93744
Step 253: 93744 + 372 = 94116
Step 254: 94116 + 372 = 94488
Step 255: 94488 + 372 = 94860
Step 256: 94860 + 372 = 95232
Step 257: 95232 + 372 = 95604
Step 258: 95604 + 372 = 95976
Step 259: 95976 + 372 = 96348
Step 260: 96348 + 372 = 96720
Step 261: 96720 + 372 = 97092
Step 262: 97092 + 372 = 97464
Step 263: 97464 + 372 = 97836
Step 264: 97836 + 372 = 98208
Step 265: 98208 + 372 = 98580
Step 266: 98580 + 372 = 98952
Step 267: 98952 + 372 = 99324
Step 268: 99324 + 372 = 99696
Step 269: 99696 + 372 = 100068
Step 270: 100068 + 372 = 100440
Step 271: 100440 + 372 = 100812
Step 272: 100812 + 372 = 101184
Step 273: 101184 + 372 = 101556
Step 274: 101556 + 372 = 101928
Step 275: 101928 + 372 = 102300
Step 276: 102300 + 372 = 102672
Step 277: 102672 + 372 = 103044
Step 278: 103044 + 372 = 103416
Step 279: 103416 + 372 = 103788
Step 280: 103788 + 372 = 104160
Step 281: 104160 + 372 = 104532
Step 282: 104532 + 372 = 104904
Step 283: 104904 + 372 = 105276
Step 284: 105276 + 372 = 105648
Step 285: 105648 + 372 = 106020
Step 286: 106020 + 372 = 106392
Step 287: 106392 + 372 = 106764
Step 288: 106764 + 372 = 107136
Step 289: 107136 + 372 = 107508
Step 290: 107508 + 372 = 107880
Step 291: 107880 + 372 = 108252
Step 292: 108252 + 372 = 108624
Step 293: 108624 + 372 = 108996
Step 294: 108996 + 372 = 109368
Step 295: 109368 + 372 = 109740
Step 296: 109740 + 372 = 110112
Step 297: 110112 + 372 = 110484
Step 298: 110484 + 372 = 110856
Step 299: 110856 + 372 = 111228
Step 300: 111228 + 372 = 111600
Step 301: 111600 + 372 = 111972
Step 302: 111972 + 372 = 112344
Step 303: 112344 + 372 = 112716
Step 304: 112716 + 372 = 113088
Step 305: 113088 + 372 = 113460
Step 306: 113460 + 372 = 113832
Step 307: 113832 + 372 = 114204
Step 308: 114204 + 372 = 114576
Step 309: 114576 + 372 = 114948
Step 310: 114948 + 372 = 115320
Step 311: 115320 + 372 = 115692
Step 312: 115692 + 372 = 116064
Step 313: 116064 + 372 = 116436
Step 314: 116436 + 372 = 116808
Step 315: 116808 + 372 = 117180
Step 316: 117180 + 372 = 117552
Step 317: 117552 + 372 = 117924
Step 318: 117924 + 372 = 118296
Step 319: 118296 + 372 = 118668
Step 320: 118668 + 372 = 119040
Step 321: 119040 + 372 = 119412
Step 322: 119412 + 372 = 119784
Step 323: 119784 + 372 = 120156
Step 324: 120156 + 372 = 120528
Step 325: 120528 + 372 = 120900
Step 326: 120900 + 372 = 121272
Step 327: 121272 + 372 = 121644
Step 328: 121644 + 372 = 122016
Step 329: 122016 + 372 = 122388
Step 330: 122388 + 372 = 122760
Step 331: 122760 + 372 = 123132
Step 332: 123132 + 372 = 123504
Step 333: 123504 + 372 = 123876
Step 334: 123876 + 372 = 124248
Step 335: 124248 + 372 = 124620
Step 336: 124620 + 372 = 124992
Step 337: 124992 + 372 = 125364
Step 338: 125364 + 372 = 125736
Step 339: 125736 + 372 = 126108
Step 340: 126108 + 372 = 126480
Step 341: 126480 + 372 = 126852
Step 342: 126852 + 372 = 127224
Step 343: 127224 + 372 = 127596
Step 344: 127596 + 372 = 127968
Step 345: 127968 + 372 = 128340
Step 346: 128340 + 372 = 128712
Step 347: 128712 + 372 = 129084
Step 348: 129084 + 372 = 129456
Step 349: 129456 + 372 = 129828
Step 350: 129828 + 372 = 130200
Step 351: 130200 + 372 = 130572
Step 352: 130572 + 372 = 130944
Step 353: 130944 + 372 = 131316
Step 354: 131316 + 372 = 131688
Step 355: 131688 + 372 = 132060
Step 356: 132060 + 372 = 132432
Step 357: 132432 + 372 = 132804
Step 358: 132804 + 372 = 133176
Step 359: 133176 + 372 = 133548
Step 360: 133548 + 372 = 133920
Step 361: 133920 + 372 = 134292
Step 362: 134292 + 372 = 134664
Step 363: 134664 + 372 = 135036
Step 364: 135036 + 372 = 135408
Step 365: 135408 + 372 = 135780
Step 366: 135780 + 372 = 136152
Step 367: 136152 + 372 = 136524
Step 368: 136524 + 372 = 136896
Step 369: 136896 + 372 = 137268
Step 370: 137268 + 372 = 137640
Step 371: 137640 + 372 = 138012
Step 372: 138012 + 372 = 138384
Step 373: 138384 + 372 = 138756
Step 374: 138756 + 372 = 139128
Step 375: 139128 + 372 = 139500
Step 376: 139500 + 372 = 139872
Step 377: 139872 + 372 = 140244
Step 378: 140244 + 372 = 140616
Step 379: 140616 + 372 = 140988
Step 380: 140988 + 372 = 141360
Step 381: 141360 + 372 = 141732
Step 382: 141732 + 372 = 142104
Step 383: 142104 + 372 = 142476
Step 384: 142476 + 372 = 142848
Step 385: 142848 + 372 = 143220
Step 386: 143220 + 372 = 143592
Step 387: 143592 + 372 = 143964
Step 388: 143964 + 372 = 144336
Step 389: 144336 + 372 = 144708
Step 390: 144708 + 372 = 145080
Step 391: 145080 + 372 = 145452
Step 392: 145452 + 372 = 145824
Step 393: 145824 + 372 = 146196
Step 394: 146196 + 372 = 146568
Step 395: 146568 + 372 = 146940
Step 396: 146940 + 372 = 147312
Step 397: 147312 + 372 = 147684
Step 398: 147684 + 372 = 148056
Step 399: 148056 + 372 = 148428
Step 400: 148428 + 372 = 148800
Step 401: 148800 + 372 = 149172
Step 402: 149172 + 372 = 149544
Step 403: 149544 + 372 = 149916
Step 404: 149916 + 372 = 150288
Step 405: 150288 + 372 = 150660
Step 406: 150660 + 372 = 151032
Step 407: 151032 + 372 = 151404
Step 408: 151404 + 372 = 151776
Step 409: 151776 + 372 = 152148
Step 410: 152148 + 372 = 152520
Step 411: 152520 + 372 = 152892
Step 412: 152892 + 372 = 153264
Step 413: 153264 + 372 = 153636
Step 414: 153636 + 372 = 154008
Step 415: 154008 + 372 = 154380
Step 416: 154380 + 372 = 154752
Step 417: 154752 + 372 = 155124
Step 418: 155124 + 372 = 155496
Step 419: 155496 + 372 = 155868
Step 420: 155868 + 372 = 156240

So, 372*420 = 156240