Alright, let's solve this math problem step by step. First, we have the number 399. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 344. So, we're going to take the number 399 and add it to itself 344 times.
Step 1: 0 + 399 = 399
Step 2: 399 + 399 = 798
Step 3: 798 + 399 = 1197
Step 4: 1197 + 399 = 1596
Step 5: 1596 + 399 = 1995
Step 6: 1995 + 399 = 2394
Step 7: 2394 + 399 = 2793
Step 8: 2793 + 399 = 3192
Step 9: 3192 + 399 = 3591
Step 10: 3591 + 399 = 3990
Step 11: 3990 + 399 = 4389
Step 12: 4389 + 399 = 4788
Step 13: 4788 + 399 = 5187
Step 14: 5187 + 399 = 5586
Step 15: 5586 + 399 = 5985
Step 16: 5985 + 399 = 6384
Step 17: 6384 + 399 = 6783
Step 18: 6783 + 399 = 7182
Step 19: 7182 + 399 = 7581
Step 20: 7581 + 399 = 7980
Step 21: 7980 + 399 = 8379
Step 22: 8379 + 399 = 8778
Step 23: 8778 + 399 = 9177
Step 24: 9177 + 399 = 9576
Step 25: 9576 + 399 = 9975
Step 26: 9975 + 399 = 10374
Step 27: 10374 + 399 = 10773
Step 28: 10773 + 399 = 11172
Step 29: 11172 + 399 = 11571
Step 30: 11571 + 399 = 11970
Step 31: 11970 + 399 = 12369
Step 32: 12369 + 399 = 12768
Step 33: 12768 + 399 = 13167
Step 34: 13167 + 399 = 13566
Step 35: 13566 + 399 = 13965
Step 36: 13965 + 399 = 14364
Step 37: 14364 + 399 = 14763
Step 38: 14763 + 399 = 15162
Step 39: 15162 + 399 = 15561
Step 40: 15561 + 399 = 15960
Step 41: 15960 + 399 = 16359
Step 42: 16359 + 399 = 16758
Step 43: 16758 + 399 = 17157
Step 44: 17157 + 399 = 17556
Step 45: 17556 + 399 = 17955
Step 46: 17955 + 399 = 18354
Step 47: 18354 + 399 = 18753
Step 48: 18753 + 399 = 19152
Step 49: 19152 + 399 = 19551
Step 50: 19551 + 399 = 19950
Step 51: 19950 + 399 = 20349
Step 52: 20349 + 399 = 20748
Step 53: 20748 + 399 = 21147
Step 54: 21147 + 399 = 21546
Step 55: 21546 + 399 = 21945
Step 56: 21945 + 399 = 22344
Step 57: 22344 + 399 = 22743
Step 58: 22743 + 399 = 23142
Step 59: 23142 + 399 = 23541
Step 60: 23541 + 399 = 23940
Step 61: 23940 + 399 = 24339
Step 62: 24339 + 399 = 24738
Step 63: 24738 + 399 = 25137
Step 64: 25137 + 399 = 25536
Step 65: 25536 + 399 = 25935
Step 66: 25935 + 399 = 26334
Step 67: 26334 + 399 = 26733
Step 68: 26733 + 399 = 27132
Step 69: 27132 + 399 = 27531
Step 70: 27531 + 399 = 27930
Step 71: 27930 + 399 = 28329
Step 72: 28329 + 399 = 28728
Step 73: 28728 + 399 = 29127
Step 74: 29127 + 399 = 29526
Step 75: 29526 + 399 = 29925
Step 76: 29925 + 399 = 30324
Step 77: 30324 + 399 = 30723
Step 78: 30723 + 399 = 31122
Step 79: 31122 + 399 = 31521
Step 80: 31521 + 399 = 31920
Step 81: 31920 + 399 = 32319
Step 82: 32319 + 399 = 32718
Step 83: 32718 + 399 = 33117
Step 84: 33117 + 399 = 33516
Step 85: 33516 + 399 = 33915
Step 86: 33915 + 399 = 34314
Step 87: 34314 + 399 = 34713
Step 88: 34713 + 399 = 35112
Step 89: 35112 + 399 = 35511
Step 90: 35511 + 399 = 35910
Step 91: 35910 + 399 = 36309
Step 92: 36309 + 399 = 36708
Step 93: 36708 + 399 = 37107
Step 94: 37107 + 399 = 37506
Step 95: 37506 + 399 = 37905
Step 96: 37905 + 399 = 38304
Step 97: 38304 + 399 = 38703
Step 98: 38703 + 399 = 39102
Step 99: 39102 + 399 = 39501
Step 100: 39501 + 399 = 39900
Step 101: 39900 + 399 = 40299
Step 102: 40299 + 399 = 40698
Step 103: 40698 + 399 = 41097
Step 104: 41097 + 399 = 41496
Step 105: 41496 + 399 = 41895
Step 106: 41895 + 399 = 42294
Step 107: 42294 + 399 = 42693
Step 108: 42693 + 399 = 43092
Step 109: 43092 + 399 = 43491
Step 110: 43491 + 399 = 43890
Step 111: 43890 + 399 = 44289
Step 112: 44289 + 399 = 44688
Step 113: 44688 + 399 = 45087
Step 114: 45087 + 399 = 45486
Step 115: 45486 + 399 = 45885
Step 116: 45885 + 399 = 46284
Step 117: 46284 + 399 = 46683
Step 118: 46683 + 399 = 47082
Step 119: 47082 + 399 = 47481
Step 120: 47481 + 399 = 47880
Step 121: 47880 + 399 = 48279
Step 122: 48279 + 399 = 48678
Step 123: 48678 + 399 = 49077
Step 124: 49077 + 399 = 49476
Step 125: 49476 + 399 = 49875
Step 126: 49875 + 399 = 50274
Step 127: 50274 + 399 = 50673
Step 128: 50673 + 399 = 51072
Step 129: 51072 + 399 = 51471
Step 130: 51471 + 399 = 51870
Step 131: 51870 + 399 = 52269
Step 132: 52269 + 399 = 52668
Step 133: 52668 + 399 = 53067
Step 134: 53067 + 399 = 53466
Step 135: 53466 + 399 = 53865
Step 136: 53865 + 399 = 54264
Step 137: 54264 + 399 = 54663
Step 138: 54663 + 399 = 55062
Step 139: 55062 + 399 = 55461
Step 140: 55461 + 399 = 55860
Step 141: 55860 + 399 = 56259
Step 142: 56259 + 399 = 56658
Step 143: 56658 + 399 = 57057
Step 144: 57057 + 399 = 57456
Step 145: 57456 + 399 = 57855
Step 146: 57855 + 399 = 58254
Step 147: 58254 + 399 = 58653
Step 148: 58653 + 399 = 59052
Step 149: 59052 + 399 = 59451
Step 150: 59451 + 399 = 59850
Step 151: 59850 + 399 = 60249
Step 152: 60249 + 399 = 60648
Step 153: 60648 + 399 = 61047
Step 154: 61047 + 399 = 61446
Step 155: 61446 + 399 = 61845
Step 156: 61845 + 399 = 62244
Step 157: 62244 + 399 = 62643
Step 158: 62643 + 399 = 63042
Step 159: 63042 + 399 = 63441
Step 160: 63441 + 399 = 63840
Step 161: 63840 + 399 = 64239
Step 162: 64239 + 399 = 64638
Step 163: 64638 + 399 = 65037
Step 164: 65037 + 399 = 65436
Step 165: 65436 + 399 = 65835
Step 166: 65835 + 399 = 66234
Step 167: 66234 + 399 = 66633
Step 168: 66633 + 399 = 67032
Step 169: 67032 + 399 = 67431
Step 170: 67431 + 399 = 67830
Step 171: 67830 + 399 = 68229
Step 172: 68229 + 399 = 68628
Step 173: 68628 + 399 = 69027
Step 174: 69027 + 399 = 69426
Step 175: 69426 + 399 = 69825
Step 176: 69825 + 399 = 70224
Step 177: 70224 + 399 = 70623
Step 178: 70623 + 399 = 71022
Step 179: 71022 + 399 = 71421
Step 180: 71421 + 399 = 71820
Step 181: 71820 + 399 = 72219
Step 182: 72219 + 399 = 72618
Step 183: 72618 + 399 = 73017
Step 184: 73017 + 399 = 73416
Step 185: 73416 + 399 = 73815
Step 186: 73815 + 399 = 74214
Step 187: 74214 + 399 = 74613
Step 188: 74613 + 399 = 75012
Step 189: 75012 + 399 = 75411
Step 190: 75411 + 399 = 75810
Step 191: 75810 + 399 = 76209
Step 192: 76209 + 399 = 76608
Step 193: 76608 + 399 = 77007
Step 194: 77007 + 399 = 77406
Step 195: 77406 + 399 = 77805
Step 196: 77805 + 399 = 78204
Step 197: 78204 + 399 = 78603
Step 198: 78603 + 399 = 79002
Step 199: 79002 + 399 = 79401
Step 200: 79401 + 399 = 79800
Step 201: 79800 + 399 = 80199
Step 202: 80199 + 399 = 80598
Step 203: 80598 + 399 = 80997
Step 204: 80997 + 399 = 81396
Step 205: 81396 + 399 = 81795
Step 206: 81795 + 399 = 82194
Step 207: 82194 + 399 = 82593
Step 208: 82593 + 399 = 82992
Step 209: 82992 + 399 = 83391
Step 210: 83391 + 399 = 83790
Step 211: 83790 + 399 = 84189
Step 212: 84189 + 399 = 84588
Step 213: 84588 + 399 = 84987
Step 214: 84987 + 399 = 85386
Step 215: 85386 + 399 = 85785
Step 216: 85785 + 399 = 86184
Step 217: 86184 + 399 = 86583
Step 218: 86583 + 399 = 86982
Step 219: 86982 + 399 = 87381
Step 220: 87381 + 399 = 87780
Step 221: 87780 + 399 = 88179
Step 222: 88179 + 399 = 88578
Step 223: 88578 + 399 = 88977
Step 224: 88977 + 399 = 89376
Step 225: 89376 + 399 = 89775
Step 226: 89775 + 399 = 90174
Step 227: 90174 + 399 = 90573
Step 228: 90573 + 399 = 90972
Step 229: 90972 + 399 = 91371
Step 230: 91371 + 399 = 91770
Step 231: 91770 + 399 = 92169
Step 232: 92169 + 399 = 92568
Step 233: 92568 + 399 = 92967
Step 234: 92967 + 399 = 93366
Step 235: 93366 + 399 = 93765
Step 236: 93765 + 399 = 94164
Step 237: 94164 + 399 = 94563
Step 238: 94563 + 399 = 94962
Step 239: 94962 + 399 = 95361
Step 240: 95361 + 399 = 95760
Step 241: 95760 + 399 = 96159
Step 242: 96159 + 399 = 96558
Step 243: 96558 + 399 = 96957
Step 244: 96957 + 399 = 97356
Step 245: 97356 + 399 = 97755
Step 246: 97755 + 399 = 98154
Step 247: 98154 + 399 = 98553
Step 248: 98553 + 399 = 98952
Step 249: 98952 + 399 = 99351
Step 250: 99351 + 399 = 99750
Step 251: 99750 + 399 = 100149
Step 252: 100149 + 399 = 100548
Step 253: 100548 + 399 = 100947
Step 254: 100947 + 399 = 101346
Step 255: 101346 + 399 = 101745
Step 256: 101745 + 399 = 102144
Step 257: 102144 + 399 = 102543
Step 258: 102543 + 399 = 102942
Step 259: 102942 + 399 = 103341
Step 260: 103341 + 399 = 103740
Step 261: 103740 + 399 = 104139
Step 262: 104139 + 399 = 104538
Step 263: 104538 + 399 = 104937
Step 264: 104937 + 399 = 105336
Step 265: 105336 + 399 = 105735
Step 266: 105735 + 399 = 106134
Step 267: 106134 + 399 = 106533
Step 268: 106533 + 399 = 106932
Step 269: 106932 + 399 = 107331
Step 270: 107331 + 399 = 107730
Step 271: 107730 + 399 = 108129
Step 272: 108129 + 399 = 108528
Step 273: 108528 + 399 = 108927
Step 274: 108927 + 399 = 109326
Step 275: 109326 + 399 = 109725
Step 276: 109725 + 399 = 110124
Step 277: 110124 + 399 = 110523
Step 278: 110523 + 399 = 110922
Step 279: 110922 + 399 = 111321
Step 280: 111321 + 399 = 111720
Step 281: 111720 + 399 = 112119
Step 282: 112119 + 399 = 112518
Step 283: 112518 + 399 = 112917
Step 284: 112917 + 399 = 113316
Step 285: 113316 + 399 = 113715
Step 286: 113715 + 399 = 114114
Step 287: 114114 + 399 = 114513
Step 288: 114513 + 399 = 114912
Step 289: 114912 + 399 = 115311
Step 290: 115311 + 399 = 115710
Step 291: 115710 + 399 = 116109
Step 292: 116109 + 399 = 116508
Step 293: 116508 + 399 = 116907
Step 294: 116907 + 399 = 117306
Step 295: 117306 + 399 = 117705
Step 296: 117705 + 399 = 118104
Step 297: 118104 + 399 = 118503
Step 298: 118503 + 399 = 118902
Step 299: 118902 + 399 = 119301
Step 300: 119301 + 399 = 119700
Step 301: 119700 + 399 = 120099
Step 302: 120099 + 399 = 120498
Step 303: 120498 + 399 = 120897
Step 304: 120897 + 399 = 121296
Step 305: 121296 + 399 = 121695
Step 306: 121695 + 399 = 122094
Step 307: 122094 + 399 = 122493
Step 308: 122493 + 399 = 122892
Step 309: 122892 + 399 = 123291
Step 310: 123291 + 399 = 123690
Step 311: 123690 + 399 = 124089
Step 312: 124089 + 399 = 124488
Step 313: 124488 + 399 = 124887
Step 314: 124887 + 399 = 125286
Step 315: 125286 + 399 = 125685
Step 316: 125685 + 399 = 126084
Step 317: 126084 + 399 = 126483
Step 318: 126483 + 399 = 126882
Step 319: 126882 + 399 = 127281
Step 320: 127281 + 399 = 127680
Step 321: 127680 + 399 = 128079
Step 322: 128079 + 399 = 128478
Step 323: 128478 + 399 = 128877
Step 324: 128877 + 399 = 129276
Step 325: 129276 + 399 = 129675
Step 326: 129675 + 399 = 130074
Step 327: 130074 + 399 = 130473
Step 328: 130473 + 399 = 130872
Step 329: 130872 + 399 = 131271
Step 330: 131271 + 399 = 131670
Step 331: 131670 + 399 = 132069
Step 332: 132069 + 399 = 132468
Step 333: 132468 + 399 = 132867
Step 334: 132867 + 399 = 133266
Step 335: 133266 + 399 = 133665
Step 336: 133665 + 399 = 134064
Step 337: 134064 + 399 = 134463
Step 338: 134463 + 399 = 134862
Step 339: 134862 + 399 = 135261
Step 340: 135261 + 399 = 135660
Step 341: 135660 + 399 = 136059
Step 342: 136059 + 399 = 136458
Step 343: 136458 + 399 = 136857
Step 344: 136857 + 399 = 137256

So, 399*344 = 137256