Let's roll up our sleeves and solve this. We have 371 and we're going to multiply it by 55, essentially adding 371 to itself 55 times.
Step 1: 0 + 371 = 371
Step 2: 371 + 371 = 742
Step 3: 742 + 371 = 1113
Step 4: 1113 + 371 = 1484
Step 5: 1484 + 371 = 1855
Step 6: 1855 + 371 = 2226
Step 7: 2226 + 371 = 2597
Step 8: 2597 + 371 = 2968
Step 9: 2968 + 371 = 3339
Step 10: 3339 + 371 = 3710
Step 11: 3710 + 371 = 4081
Step 12: 4081 + 371 = 4452
Step 13: 4452 + 371 = 4823
Step 14: 4823 + 371 = 5194
Step 15: 5194 + 371 = 5565
Step 16: 5565 + 371 = 5936
Step 17: 5936 + 371 = 6307
Step 18: 6307 + 371 = 6678
Step 19: 6678 + 371 = 7049
Step 20: 7049 + 371 = 7420
Step 21: 7420 + 371 = 7791
Step 22: 7791 + 371 = 8162
Step 23: 8162 + 371 = 8533
Step 24: 8533 + 371 = 8904
Step 25: 8904 + 371 = 9275
Step 26: 9275 + 371 = 9646
Step 27: 9646 + 371 = 10017
Step 28: 10017 + 371 = 10388
Step 29: 10388 + 371 = 10759
Step 30: 10759 + 371 = 11130
Step 31: 11130 + 371 = 11501
Step 32: 11501 + 371 = 11872
Step 33: 11872 + 371 = 12243
Step 34: 12243 + 371 = 12614
Step 35: 12614 + 371 = 12985
Step 36: 12985 + 371 = 13356
Step 37: 13356 + 371 = 13727
Step 38: 13727 + 371 = 14098
Step 39: 14098 + 371 = 14469
Step 40: 14469 + 371 = 14840
Step 41: 14840 + 371 = 15211
Step 42: 15211 + 371 = 15582
Step 43: 15582 + 371 = 15953
Step 44: 15953 + 371 = 16324
Step 45: 16324 + 371 = 16695
Step 46: 16695 + 371 = 17066
Step 47: 17066 + 371 = 17437
Step 48: 17437 + 371 = 17808
Step 49: 17808 + 371 = 18179
Step 50: 18179 + 371 = 18550
Step 51: 18550 + 371 = 18921
Step 52: 18921 + 371 = 19292
Step 53: 19292 + 371 = 19663
Step 54: 19663 + 371 = 20034
Step 55: 20034 + 371 = 20405

So, 371*55 = 20405