Let's get this math done. We have 431 and we're going to multiply it by 320. This is the same as taking 431 and adding it to itself 320 times.
Step 1: 0 + 431 = 431
Step 2: 431 + 431 = 862
Step 3: 862 + 431 = 1293
Step 4: 1293 + 431 = 1724
Step 5: 1724 + 431 = 2155
Step 6: 2155 + 431 = 2586
Step 7: 2586 + 431 = 3017
Step 8: 3017 + 431 = 3448
Step 9: 3448 + 431 = 3879
Step 10: 3879 + 431 = 4310
Step 11: 4310 + 431 = 4741
Step 12: 4741 + 431 = 5172
Step 13: 5172 + 431 = 5603
Step 14: 5603 + 431 = 6034
Step 15: 6034 + 431 = 6465
Step 16: 6465 + 431 = 6896
Step 17: 6896 + 431 = 7327
Step 18: 7327 + 431 = 7758
Step 19: 7758 + 431 = 8189
Step 20: 8189 + 431 = 8620
Step 21: 8620 + 431 = 9051
Step 22: 9051 + 431 = 9482
Step 23: 9482 + 431 = 9913
Step 24: 9913 + 431 = 10344
Step 25: 10344 + 431 = 10775
Step 26: 10775 + 431 = 11206
Step 27: 11206 + 431 = 11637
Step 28: 11637 + 431 = 12068
Step 29: 12068 + 431 = 12499
Step 30: 12499 + 431 = 12930
Step 31: 12930 + 431 = 13361
Step 32: 13361 + 431 = 13792
Step 33: 13792 + 431 = 14223
Step 34: 14223 + 431 = 14654
Step 35: 14654 + 431 = 15085
Step 36: 15085 + 431 = 15516
Step 37: 15516 + 431 = 15947
Step 38: 15947 + 431 = 16378
Step 39: 16378 + 431 = 16809
Step 40: 16809 + 431 = 17240
Step 41: 17240 + 431 = 17671
Step 42: 17671 + 431 = 18102
Step 43: 18102 + 431 = 18533
Step 44: 18533 + 431 = 18964
Step 45: 18964 + 431 = 19395
Step 46: 19395 + 431 = 19826
Step 47: 19826 + 431 = 20257
Step 48: 20257 + 431 = 20688
Step 49: 20688 + 431 = 21119
Step 50: 21119 + 431 = 21550
Step 51: 21550 + 431 = 21981
Step 52: 21981 + 431 = 22412
Step 53: 22412 + 431 = 22843
Step 54: 22843 + 431 = 23274
Step 55: 23274 + 431 = 23705
Step 56: 23705 + 431 = 24136
Step 57: 24136 + 431 = 24567
Step 58: 24567 + 431 = 24998
Step 59: 24998 + 431 = 25429
Step 60: 25429 + 431 = 25860
Step 61: 25860 + 431 = 26291
Step 62: 26291 + 431 = 26722
Step 63: 26722 + 431 = 27153
Step 64: 27153 + 431 = 27584
Step 65: 27584 + 431 = 28015
Step 66: 28015 + 431 = 28446
Step 67: 28446 + 431 = 28877
Step 68: 28877 + 431 = 29308
Step 69: 29308 + 431 = 29739
Step 70: 29739 + 431 = 30170
Step 71: 30170 + 431 = 30601
Step 72: 30601 + 431 = 31032
Step 73: 31032 + 431 = 31463
Step 74: 31463 + 431 = 31894
Step 75: 31894 + 431 = 32325
Step 76: 32325 + 431 = 32756
Step 77: 32756 + 431 = 33187
Step 78: 33187 + 431 = 33618
Step 79: 33618 + 431 = 34049
Step 80: 34049 + 431 = 34480
Step 81: 34480 + 431 = 34911
Step 82: 34911 + 431 = 35342
Step 83: 35342 + 431 = 35773
Step 84: 35773 + 431 = 36204
Step 85: 36204 + 431 = 36635
Step 86: 36635 + 431 = 37066
Step 87: 37066 + 431 = 37497
Step 88: 37497 + 431 = 37928
Step 89: 37928 + 431 = 38359
Step 90: 38359 + 431 = 38790
Step 91: 38790 + 431 = 39221
Step 92: 39221 + 431 = 39652
Step 93: 39652 + 431 = 40083
Step 94: 40083 + 431 = 40514
Step 95: 40514 + 431 = 40945
Step 96: 40945 + 431 = 41376
Step 97: 41376 + 431 = 41807
Step 98: 41807 + 431 = 42238
Step 99: 42238 + 431 = 42669
Step 100: 42669 + 431 = 43100
Step 101: 43100 + 431 = 43531
Step 102: 43531 + 431 = 43962
Step 103: 43962 + 431 = 44393
Step 104: 44393 + 431 = 44824
Step 105: 44824 + 431 = 45255
Step 106: 45255 + 431 = 45686
Step 107: 45686 + 431 = 46117
Step 108: 46117 + 431 = 46548
Step 109: 46548 + 431 = 46979
Step 110: 46979 + 431 = 47410
Step 111: 47410 + 431 = 47841
Step 112: 47841 + 431 = 48272
Step 113: 48272 + 431 = 48703
Step 114: 48703 + 431 = 49134
Step 115: 49134 + 431 = 49565
Step 116: 49565 + 431 = 49996
Step 117: 49996 + 431 = 50427
Step 118: 50427 + 431 = 50858
Step 119: 50858 + 431 = 51289
Step 120: 51289 + 431 = 51720
Step 121: 51720 + 431 = 52151
Step 122: 52151 + 431 = 52582
Step 123: 52582 + 431 = 53013
Step 124: 53013 + 431 = 53444
Step 125: 53444 + 431 = 53875
Step 126: 53875 + 431 = 54306
Step 127: 54306 + 431 = 54737
Step 128: 54737 + 431 = 55168
Step 129: 55168 + 431 = 55599
Step 130: 55599 + 431 = 56030
Step 131: 56030 + 431 = 56461
Step 132: 56461 + 431 = 56892
Step 133: 56892 + 431 = 57323
Step 134: 57323 + 431 = 57754
Step 135: 57754 + 431 = 58185
Step 136: 58185 + 431 = 58616
Step 137: 58616 + 431 = 59047
Step 138: 59047 + 431 = 59478
Step 139: 59478 + 431 = 59909
Step 140: 59909 + 431 = 60340
Step 141: 60340 + 431 = 60771
Step 142: 60771 + 431 = 61202
Step 143: 61202 + 431 = 61633
Step 144: 61633 + 431 = 62064
Step 145: 62064 + 431 = 62495
Step 146: 62495 + 431 = 62926
Step 147: 62926 + 431 = 63357
Step 148: 63357 + 431 = 63788
Step 149: 63788 + 431 = 64219
Step 150: 64219 + 431 = 64650
Step 151: 64650 + 431 = 65081
Step 152: 65081 + 431 = 65512
Step 153: 65512 + 431 = 65943
Step 154: 65943 + 431 = 66374
Step 155: 66374 + 431 = 66805
Step 156: 66805 + 431 = 67236
Step 157: 67236 + 431 = 67667
Step 158: 67667 + 431 = 68098
Step 159: 68098 + 431 = 68529
Step 160: 68529 + 431 = 68960
Step 161: 68960 + 431 = 69391
Step 162: 69391 + 431 = 69822
Step 163: 69822 + 431 = 70253
Step 164: 70253 + 431 = 70684
Step 165: 70684 + 431 = 71115
Step 166: 71115 + 431 = 71546
Step 167: 71546 + 431 = 71977
Step 168: 71977 + 431 = 72408
Step 169: 72408 + 431 = 72839
Step 170: 72839 + 431 = 73270
Step 171: 73270 + 431 = 73701
Step 172: 73701 + 431 = 74132
Step 173: 74132 + 431 = 74563
Step 174: 74563 + 431 = 74994
Step 175: 74994 + 431 = 75425
Step 176: 75425 + 431 = 75856
Step 177: 75856 + 431 = 76287
Step 178: 76287 + 431 = 76718
Step 179: 76718 + 431 = 77149
Step 180: 77149 + 431 = 77580
Step 181: 77580 + 431 = 78011
Step 182: 78011 + 431 = 78442
Step 183: 78442 + 431 = 78873
Step 184: 78873 + 431 = 79304
Step 185: 79304 + 431 = 79735
Step 186: 79735 + 431 = 80166
Step 187: 80166 + 431 = 80597
Step 188: 80597 + 431 = 81028
Step 189: 81028 + 431 = 81459
Step 190: 81459 + 431 = 81890
Step 191: 81890 + 431 = 82321
Step 192: 82321 + 431 = 82752
Step 193: 82752 + 431 = 83183
Step 194: 83183 + 431 = 83614
Step 195: 83614 + 431 = 84045
Step 196: 84045 + 431 = 84476
Step 197: 84476 + 431 = 84907
Step 198: 84907 + 431 = 85338
Step 199: 85338 + 431 = 85769
Step 200: 85769 + 431 = 86200
Step 201: 86200 + 431 = 86631
Step 202: 86631 + 431 = 87062
Step 203: 87062 + 431 = 87493
Step 204: 87493 + 431 = 87924
Step 205: 87924 + 431 = 88355
Step 206: 88355 + 431 = 88786
Step 207: 88786 + 431 = 89217
Step 208: 89217 + 431 = 89648
Step 209: 89648 + 431 = 90079
Step 210: 90079 + 431 = 90510
Step 211: 90510 + 431 = 90941
Step 212: 90941 + 431 = 91372
Step 213: 91372 + 431 = 91803
Step 214: 91803 + 431 = 92234
Step 215: 92234 + 431 = 92665
Step 216: 92665 + 431 = 93096
Step 217: 93096 + 431 = 93527
Step 218: 93527 + 431 = 93958
Step 219: 93958 + 431 = 94389
Step 220: 94389 + 431 = 94820
Step 221: 94820 + 431 = 95251
Step 222: 95251 + 431 = 95682
Step 223: 95682 + 431 = 96113
Step 224: 96113 + 431 = 96544
Step 225: 96544 + 431 = 96975
Step 226: 96975 + 431 = 97406
Step 227: 97406 + 431 = 97837
Step 228: 97837 + 431 = 98268
Step 229: 98268 + 431 = 98699
Step 230: 98699 + 431 = 99130
Step 231: 99130 + 431 = 99561
Step 232: 99561 + 431 = 99992
Step 233: 99992 + 431 = 100423
Step 234: 100423 + 431 = 100854
Step 235: 100854 + 431 = 101285
Step 236: 101285 + 431 = 101716
Step 237: 101716 + 431 = 102147
Step 238: 102147 + 431 = 102578
Step 239: 102578 + 431 = 103009
Step 240: 103009 + 431 = 103440
Step 241: 103440 + 431 = 103871
Step 242: 103871 + 431 = 104302
Step 243: 104302 + 431 = 104733
Step 244: 104733 + 431 = 105164
Step 245: 105164 + 431 = 105595
Step 246: 105595 + 431 = 106026
Step 247: 106026 + 431 = 106457
Step 248: 106457 + 431 = 106888
Step 249: 106888 + 431 = 107319
Step 250: 107319 + 431 = 107750
Step 251: 107750 + 431 = 108181
Step 252: 108181 + 431 = 108612
Step 253: 108612 + 431 = 109043
Step 254: 109043 + 431 = 109474
Step 255: 109474 + 431 = 109905
Step 256: 109905 + 431 = 110336
Step 257: 110336 + 431 = 110767
Step 258: 110767 + 431 = 111198
Step 259: 111198 + 431 = 111629
Step 260: 111629 + 431 = 112060
Step 261: 112060 + 431 = 112491
Step 262: 112491 + 431 = 112922
Step 263: 112922 + 431 = 113353
Step 264: 113353 + 431 = 113784
Step 265: 113784 + 431 = 114215
Step 266: 114215 + 431 = 114646
Step 267: 114646 + 431 = 115077
Step 268: 115077 + 431 = 115508
Step 269: 115508 + 431 = 115939
Step 270: 115939 + 431 = 116370
Step 271: 116370 + 431 = 116801
Step 272: 116801 + 431 = 117232
Step 273: 117232 + 431 = 117663
Step 274: 117663 + 431 = 118094
Step 275: 118094 + 431 = 118525
Step 276: 118525 + 431 = 118956
Step 277: 118956 + 431 = 119387
Step 278: 119387 + 431 = 119818
Step 279: 119818 + 431 = 120249
Step 280: 120249 + 431 = 120680
Step 281: 120680 + 431 = 121111
Step 282: 121111 + 431 = 121542
Step 283: 121542 + 431 = 121973
Step 284: 121973 + 431 = 122404
Step 285: 122404 + 431 = 122835
Step 286: 122835 + 431 = 123266
Step 287: 123266 + 431 = 123697
Step 288: 123697 + 431 = 124128
Step 289: 124128 + 431 = 124559
Step 290: 124559 + 431 = 124990
Step 291: 124990 + 431 = 125421
Step 292: 125421 + 431 = 125852
Step 293: 125852 + 431 = 126283
Step 294: 126283 + 431 = 126714
Step 295: 126714 + 431 = 127145
Step 296: 127145 + 431 = 127576
Step 297: 127576 + 431 = 128007
Step 298: 128007 + 431 = 128438
Step 299: 128438 + 431 = 128869
Step 300: 128869 + 431 = 129300
Step 301: 129300 + 431 = 129731
Step 302: 129731 + 431 = 130162
Step 303: 130162 + 431 = 130593
Step 304: 130593 + 431 = 131024
Step 305: 131024 + 431 = 131455
Step 306: 131455 + 431 = 131886
Step 307: 131886 + 431 = 132317
Step 308: 132317 + 431 = 132748
Step 309: 132748 + 431 = 133179
Step 310: 133179 + 431 = 133610
Step 311: 133610 + 431 = 134041
Step 312: 134041 + 431 = 134472
Step 313: 134472 + 431 = 134903
Step 314: 134903 + 431 = 135334
Step 315: 135334 + 431 = 135765
Step 316: 135765 + 431 = 136196
Step 317: 136196 + 431 = 136627
Step 318: 136627 + 431 = 137058
Step 319: 137058 + 431 = 137489
Step 320: 137489 + 431 = 137920

So, 431*320 = 137920