OK, let's work through this together. We're starting with 861 and we're going to multiply it by 88, which means we add 861 to itself 88 times.
Step 1: 0 + 861 = 861
Step 2: 861 + 861 = 1722
Step 3: 1722 + 861 = 2583
Step 4: 2583 + 861 = 3444
Step 5: 3444 + 861 = 4305
Step 6: 4305 + 861 = 5166
Step 7: 5166 + 861 = 6027
Step 8: 6027 + 861 = 6888
Step 9: 6888 + 861 = 7749
Step 10: 7749 + 861 = 8610
Step 11: 8610 + 861 = 9471
Step 12: 9471 + 861 = 10332
Step 13: 10332 + 861 = 11193
Step 14: 11193 + 861 = 12054
Step 15: 12054 + 861 = 12915
Step 16: 12915 + 861 = 13776
Step 17: 13776 + 861 = 14637
Step 18: 14637 + 861 = 15498
Step 19: 15498 + 861 = 16359
Step 20: 16359 + 861 = 17220
Step 21: 17220 + 861 = 18081
Step 22: 18081 + 861 = 18942
Step 23: 18942 + 861 = 19803
Step 24: 19803 + 861 = 20664
Step 25: 20664 + 861 = 21525
Step 26: 21525 + 861 = 22386
Step 27: 22386 + 861 = 23247
Step 28: 23247 + 861 = 24108
Step 29: 24108 + 861 = 24969
Step 30: 24969 + 861 = 25830
Step 31: 25830 + 861 = 26691
Step 32: 26691 + 861 = 27552
Step 33: 27552 + 861 = 28413
Step 34: 28413 + 861 = 29274
Step 35: 29274 + 861 = 30135
Step 36: 30135 + 861 = 30996
Step 37: 30996 + 861 = 31857
Step 38: 31857 + 861 = 32718
Step 39: 32718 + 861 = 33579
Step 40: 33579 + 861 = 34440
Step 41: 34440 + 861 = 35301
Step 42: 35301 + 861 = 36162
Step 43: 36162 + 861 = 37023
Step 44: 37023 + 861 = 37884
Step 45: 37884 + 861 = 38745
Step 46: 38745 + 861 = 39606
Step 47: 39606 + 861 = 40467
Step 48: 40467 + 861 = 41328
Step 49: 41328 + 861 = 42189
Step 50: 42189 + 861 = 43050
Step 51: 43050 + 861 = 43911
Step 52: 43911 + 861 = 44772
Step 53: 44772 + 861 = 45633
Step 54: 45633 + 861 = 46494
Step 55: 46494 + 861 = 47355
Step 56: 47355 + 861 = 48216
Step 57: 48216 + 861 = 49077
Step 58: 49077 + 861 = 49938
Step 59: 49938 + 861 = 50799
Step 60: 50799 + 861 = 51660
Step 61: 51660 + 861 = 52521
Step 62: 52521 + 861 = 53382
Step 63: 53382 + 861 = 54243
Step 64: 54243 + 861 = 55104
Step 65: 55104 + 861 = 55965
Step 66: 55965 + 861 = 56826
Step 67: 56826 + 861 = 57687
Step 68: 57687 + 861 = 58548
Step 69: 58548 + 861 = 59409
Step 70: 59409 + 861 = 60270
Step 71: 60270 + 861 = 61131
Step 72: 61131 + 861 = 61992
Step 73: 61992 + 861 = 62853
Step 74: 62853 + 861 = 63714
Step 75: 63714 + 861 = 64575
Step 76: 64575 + 861 = 65436
Step 77: 65436 + 861 = 66297
Step 78: 66297 + 861 = 67158
Step 79: 67158 + 861 = 68019
Step 80: 68019 + 861 = 68880
Step 81: 68880 + 861 = 69741
Step 82: 69741 + 861 = 70602
Step 83: 70602 + 861 = 71463
Step 84: 71463 + 861 = 72324
Step 85: 72324 + 861 = 73185
Step 86: 73185 + 861 = 74046
Step 87: 74046 + 861 = 74907
Step 88: 74907 + 861 = 75768

So, 861*88 = 75768