Alright, let's solve this math problem step by step. First, we have the number 987. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 91. So, we're going to take the number 987 and add it to itself 91 times.
Step 1: 0 + 987 = 987
Step 2: 987 + 987 = 1974
Step 3: 1974 + 987 = 2961
Step 4: 2961 + 987 = 3948
Step 5: 3948 + 987 = 4935
Step 6: 4935 + 987 = 5922
Step 7: 5922 + 987 = 6909
Step 8: 6909 + 987 = 7896
Step 9: 7896 + 987 = 8883
Step 10: 8883 + 987 = 9870
Step 11: 9870 + 987 = 10857
Step 12: 10857 + 987 = 11844
Step 13: 11844 + 987 = 12831
Step 14: 12831 + 987 = 13818
Step 15: 13818 + 987 = 14805
Step 16: 14805 + 987 = 15792
Step 17: 15792 + 987 = 16779
Step 18: 16779 + 987 = 17766
Step 19: 17766 + 987 = 18753
Step 20: 18753 + 987 = 19740
Step 21: 19740 + 987 = 20727
Step 22: 20727 + 987 = 21714
Step 23: 21714 + 987 = 22701
Step 24: 22701 + 987 = 23688
Step 25: 23688 + 987 = 24675
Step 26: 24675 + 987 = 25662
Step 27: 25662 + 987 = 26649
Step 28: 26649 + 987 = 27636
Step 29: 27636 + 987 = 28623
Step 30: 28623 + 987 = 29610
Step 31: 29610 + 987 = 30597
Step 32: 30597 + 987 = 31584
Step 33: 31584 + 987 = 32571
Step 34: 32571 + 987 = 33558
Step 35: 33558 + 987 = 34545
Step 36: 34545 + 987 = 35532
Step 37: 35532 + 987 = 36519
Step 38: 36519 + 987 = 37506
Step 39: 37506 + 987 = 38493
Step 40: 38493 + 987 = 39480
Step 41: 39480 + 987 = 40467
Step 42: 40467 + 987 = 41454
Step 43: 41454 + 987 = 42441
Step 44: 42441 + 987 = 43428
Step 45: 43428 + 987 = 44415
Step 46: 44415 + 987 = 45402
Step 47: 45402 + 987 = 46389
Step 48: 46389 + 987 = 47376
Step 49: 47376 + 987 = 48363
Step 50: 48363 + 987 = 49350
Step 51: 49350 + 987 = 50337
Step 52: 50337 + 987 = 51324
Step 53: 51324 + 987 = 52311
Step 54: 52311 + 987 = 53298
Step 55: 53298 + 987 = 54285
Step 56: 54285 + 987 = 55272
Step 57: 55272 + 987 = 56259
Step 58: 56259 + 987 = 57246
Step 59: 57246 + 987 = 58233
Step 60: 58233 + 987 = 59220
Step 61: 59220 + 987 = 60207
Step 62: 60207 + 987 = 61194
Step 63: 61194 + 987 = 62181
Step 64: 62181 + 987 = 63168
Step 65: 63168 + 987 = 64155
Step 66: 64155 + 987 = 65142
Step 67: 65142 + 987 = 66129
Step 68: 66129 + 987 = 67116
Step 69: 67116 + 987 = 68103
Step 70: 68103 + 987 = 69090
Step 71: 69090 + 987 = 70077
Step 72: 70077 + 987 = 71064
Step 73: 71064 + 987 = 72051
Step 74: 72051 + 987 = 73038
Step 75: 73038 + 987 = 74025
Step 76: 74025 + 987 = 75012
Step 77: 75012 + 987 = 75999
Step 78: 75999 + 987 = 76986
Step 79: 76986 + 987 = 77973
Step 80: 77973 + 987 = 78960
Step 81: 78960 + 987 = 79947
Step 82: 79947 + 987 = 80934
Step 83: 80934 + 987 = 81921
Step 84: 81921 + 987 = 82908
Step 85: 82908 + 987 = 83895
Step 86: 83895 + 987 = 84882
Step 87: 84882 + 987 = 85869
Step 88: 85869 + 987 = 86856
Step 89: 86856 + 987 = 87843
Step 90: 87843 + 987 = 88830
Step 91: 88830 + 987 = 89817

So, 987*91 = 89817