Alright, let's solve this math problem step by step. First, we have the number 121. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 172. So, we're going to take the number 121 and add it to itself 172 times.
Step 1: 0 + 121 = 121
Step 2: 121 + 121 = 242
Step 3: 242 + 121 = 363
Step 4: 363 + 121 = 484
Step 5: 484 + 121 = 605
Step 6: 605 + 121 = 726
Step 7: 726 + 121 = 847
Step 8: 847 + 121 = 968
Step 9: 968 + 121 = 1089
Step 10: 1089 + 121 = 1210
Step 11: 1210 + 121 = 1331
Step 12: 1331 + 121 = 1452
Step 13: 1452 + 121 = 1573
Step 14: 1573 + 121 = 1694
Step 15: 1694 + 121 = 1815
Step 16: 1815 + 121 = 1936
Step 17: 1936 + 121 = 2057
Step 18: 2057 + 121 = 2178
Step 19: 2178 + 121 = 2299
Step 20: 2299 + 121 = 2420
Step 21: 2420 + 121 = 2541
Step 22: 2541 + 121 = 2662
Step 23: 2662 + 121 = 2783
Step 24: 2783 + 121 = 2904
Step 25: 2904 + 121 = 3025
Step 26: 3025 + 121 = 3146
Step 27: 3146 + 121 = 3267
Step 28: 3267 + 121 = 3388
Step 29: 3388 + 121 = 3509
Step 30: 3509 + 121 = 3630
Step 31: 3630 + 121 = 3751
Step 32: 3751 + 121 = 3872
Step 33: 3872 + 121 = 3993
Step 34: 3993 + 121 = 4114
Step 35: 4114 + 121 = 4235
Step 36: 4235 + 121 = 4356
Step 37: 4356 + 121 = 4477
Step 38: 4477 + 121 = 4598
Step 39: 4598 + 121 = 4719
Step 40: 4719 + 121 = 4840
Step 41: 4840 + 121 = 4961
Step 42: 4961 + 121 = 5082
Step 43: 5082 + 121 = 5203
Step 44: 5203 + 121 = 5324
Step 45: 5324 + 121 = 5445
Step 46: 5445 + 121 = 5566
Step 47: 5566 + 121 = 5687
Step 48: 5687 + 121 = 5808
Step 49: 5808 + 121 = 5929
Step 50: 5929 + 121 = 6050
Step 51: 6050 + 121 = 6171
Step 52: 6171 + 121 = 6292
Step 53: 6292 + 121 = 6413
Step 54: 6413 + 121 = 6534
Step 55: 6534 + 121 = 6655
Step 56: 6655 + 121 = 6776
Step 57: 6776 + 121 = 6897
Step 58: 6897 + 121 = 7018
Step 59: 7018 + 121 = 7139
Step 60: 7139 + 121 = 7260
Step 61: 7260 + 121 = 7381
Step 62: 7381 + 121 = 7502
Step 63: 7502 + 121 = 7623
Step 64: 7623 + 121 = 7744
Step 65: 7744 + 121 = 7865
Step 66: 7865 + 121 = 7986
Step 67: 7986 + 121 = 8107
Step 68: 8107 + 121 = 8228
Step 69: 8228 + 121 = 8349
Step 70: 8349 + 121 = 8470
Step 71: 8470 + 121 = 8591
Step 72: 8591 + 121 = 8712
Step 73: 8712 + 121 = 8833
Step 74: 8833 + 121 = 8954
Step 75: 8954 + 121 = 9075
Step 76: 9075 + 121 = 9196
Step 77: 9196 + 121 = 9317
Step 78: 9317 + 121 = 9438
Step 79: 9438 + 121 = 9559
Step 80: 9559 + 121 = 9680
Step 81: 9680 + 121 = 9801
Step 82: 9801 + 121 = 9922
Step 83: 9922 + 121 = 10043
Step 84: 10043 + 121 = 10164
Step 85: 10164 + 121 = 10285
Step 86: 10285 + 121 = 10406
Step 87: 10406 + 121 = 10527
Step 88: 10527 + 121 = 10648
Step 89: 10648 + 121 = 10769
Step 90: 10769 + 121 = 10890
Step 91: 10890 + 121 = 11011
Step 92: 11011 + 121 = 11132
Step 93: 11132 + 121 = 11253
Step 94: 11253 + 121 = 11374
Step 95: 11374 + 121 = 11495
Step 96: 11495 + 121 = 11616
Step 97: 11616 + 121 = 11737
Step 98: 11737 + 121 = 11858
Step 99: 11858 + 121 = 11979
Step 100: 11979 + 121 = 12100
Step 101: 12100 + 121 = 12221
Step 102: 12221 + 121 = 12342
Step 103: 12342 + 121 = 12463
Step 104: 12463 + 121 = 12584
Step 105: 12584 + 121 = 12705
Step 106: 12705 + 121 = 12826
Step 107: 12826 + 121 = 12947
Step 108: 12947 + 121 = 13068
Step 109: 13068 + 121 = 13189
Step 110: 13189 + 121 = 13310
Step 111: 13310 + 121 = 13431
Step 112: 13431 + 121 = 13552
Step 113: 13552 + 121 = 13673
Step 114: 13673 + 121 = 13794
Step 115: 13794 + 121 = 13915
Step 116: 13915 + 121 = 14036
Step 117: 14036 + 121 = 14157
Step 118: 14157 + 121 = 14278
Step 119: 14278 + 121 = 14399
Step 120: 14399 + 121 = 14520
Step 121: 14520 + 121 = 14641
Step 122: 14641 + 121 = 14762
Step 123: 14762 + 121 = 14883
Step 124: 14883 + 121 = 15004
Step 125: 15004 + 121 = 15125
Step 126: 15125 + 121 = 15246
Step 127: 15246 + 121 = 15367
Step 128: 15367 + 121 = 15488
Step 129: 15488 + 121 = 15609
Step 130: 15609 + 121 = 15730
Step 131: 15730 + 121 = 15851
Step 132: 15851 + 121 = 15972
Step 133: 15972 + 121 = 16093
Step 134: 16093 + 121 = 16214
Step 135: 16214 + 121 = 16335
Step 136: 16335 + 121 = 16456
Step 137: 16456 + 121 = 16577
Step 138: 16577 + 121 = 16698
Step 139: 16698 + 121 = 16819
Step 140: 16819 + 121 = 16940
Step 141: 16940 + 121 = 17061
Step 142: 17061 + 121 = 17182
Step 143: 17182 + 121 = 17303
Step 144: 17303 + 121 = 17424
Step 145: 17424 + 121 = 17545
Step 146: 17545 + 121 = 17666
Step 147: 17666 + 121 = 17787
Step 148: 17787 + 121 = 17908
Step 149: 17908 + 121 = 18029
Step 150: 18029 + 121 = 18150
Step 151: 18150 + 121 = 18271
Step 152: 18271 + 121 = 18392
Step 153: 18392 + 121 = 18513
Step 154: 18513 + 121 = 18634
Step 155: 18634 + 121 = 18755
Step 156: 18755 + 121 = 18876
Step 157: 18876 + 121 = 18997
Step 158: 18997 + 121 = 19118
Step 159: 19118 + 121 = 19239
Step 160: 19239 + 121 = 19360
Step 161: 19360 + 121 = 19481
Step 162: 19481 + 121 = 19602
Step 163: 19602 + 121 = 19723
Step 164: 19723 + 121 = 19844
Step 165: 19844 + 121 = 19965
Step 166: 19965 + 121 = 20086
Step 167: 20086 + 121 = 20207
Step 168: 20207 + 121 = 20328
Step 169: 20328 + 121 = 20449
Step 170: 20449 + 121 = 20570
Step 171: 20570 + 121 = 20691
Step 172: 20691 + 121 = 20812

So, 121*172 = 20812