Sure thing! We've got 404 and we're gonna multiply it by 105. That's the same as adding 404 to itself 105 times.
Step 1: 0 + 404 = 404
Step 2: 404 + 404 = 808
Step 3: 808 + 404 = 1212
Step 4: 1212 + 404 = 1616
Step 5: 1616 + 404 = 2020
Step 6: 2020 + 404 = 2424
Step 7: 2424 + 404 = 2828
Step 8: 2828 + 404 = 3232
Step 9: 3232 + 404 = 3636
Step 10: 3636 + 404 = 4040
Step 11: 4040 + 404 = 4444
Step 12: 4444 + 404 = 4848
Step 13: 4848 + 404 = 5252
Step 14: 5252 + 404 = 5656
Step 15: 5656 + 404 = 6060
Step 16: 6060 + 404 = 6464
Step 17: 6464 + 404 = 6868
Step 18: 6868 + 404 = 7272
Step 19: 7272 + 404 = 7676
Step 20: 7676 + 404 = 8080
Step 21: 8080 + 404 = 8484
Step 22: 8484 + 404 = 8888
Step 23: 8888 + 404 = 9292
Step 24: 9292 + 404 = 9696
Step 25: 9696 + 404 = 10100
Step 26: 10100 + 404 = 10504
Step 27: 10504 + 404 = 10908
Step 28: 10908 + 404 = 11312
Step 29: 11312 + 404 = 11716
Step 30: 11716 + 404 = 12120
Step 31: 12120 + 404 = 12524
Step 32: 12524 + 404 = 12928
Step 33: 12928 + 404 = 13332
Step 34: 13332 + 404 = 13736
Step 35: 13736 + 404 = 14140
Step 36: 14140 + 404 = 14544
Step 37: 14544 + 404 = 14948
Step 38: 14948 + 404 = 15352
Step 39: 15352 + 404 = 15756
Step 40: 15756 + 404 = 16160
Step 41: 16160 + 404 = 16564
Step 42: 16564 + 404 = 16968
Step 43: 16968 + 404 = 17372
Step 44: 17372 + 404 = 17776
Step 45: 17776 + 404 = 18180
Step 46: 18180 + 404 = 18584
Step 47: 18584 + 404 = 18988
Step 48: 18988 + 404 = 19392
Step 49: 19392 + 404 = 19796
Step 50: 19796 + 404 = 20200
Step 51: 20200 + 404 = 20604
Step 52: 20604 + 404 = 21008
Step 53: 21008 + 404 = 21412
Step 54: 21412 + 404 = 21816
Step 55: 21816 + 404 = 22220
Step 56: 22220 + 404 = 22624
Step 57: 22624 + 404 = 23028
Step 58: 23028 + 404 = 23432
Step 59: 23432 + 404 = 23836
Step 60: 23836 + 404 = 24240
Step 61: 24240 + 404 = 24644
Step 62: 24644 + 404 = 25048
Step 63: 25048 + 404 = 25452
Step 64: 25452 + 404 = 25856
Step 65: 25856 + 404 = 26260
Step 66: 26260 + 404 = 26664
Step 67: 26664 + 404 = 27068
Step 68: 27068 + 404 = 27472
Step 69: 27472 + 404 = 27876
Step 70: 27876 + 404 = 28280
Step 71: 28280 + 404 = 28684
Step 72: 28684 + 404 = 29088
Step 73: 29088 + 404 = 29492
Step 74: 29492 + 404 = 29896
Step 75: 29896 + 404 = 30300
Step 76: 30300 + 404 = 30704
Step 77: 30704 + 404 = 31108
Step 78: 31108 + 404 = 31512
Step 79: 31512 + 404 = 31916
Step 80: 31916 + 404 = 32320
Step 81: 32320 + 404 = 32724
Step 82: 32724 + 404 = 33128
Step 83: 33128 + 404 = 33532
Step 84: 33532 + 404 = 33936
Step 85: 33936 + 404 = 34340
Step 86: 34340 + 404 = 34744
Step 87: 34744 + 404 = 35148
Step 88: 35148 + 404 = 35552
Step 89: 35552 + 404 = 35956
Step 90: 35956 + 404 = 36360
Step 91: 36360 + 404 = 36764
Step 92: 36764 + 404 = 37168
Step 93: 37168 + 404 = 37572
Step 94: 37572 + 404 = 37976
Step 95: 37976 + 404 = 38380
Step 96: 38380 + 404 = 38784
Step 97: 38784 + 404 = 39188
Step 98: 39188 + 404 = 39592
Step 99: 39592 + 404 = 39996
Step 100: 39996 + 404 = 40400
Step 101: 40400 + 404 = 40804
Step 102: 40804 + 404 = 41208
Step 103: 41208 + 404 = 41612
Step 104: 41612 + 404 = 42016
Step 105: 42016 + 404 = 42420

So, 404*105 = 42420