OK, let's work through this together. We're starting with 846 and we're going to multiply it by 75, which means we add 846 to itself 75 times.
Step 1: 0 + 846 = 846
Step 2: 846 + 846 = 1692
Step 3: 1692 + 846 = 2538
Step 4: 2538 + 846 = 3384
Step 5: 3384 + 846 = 4230
Step 6: 4230 + 846 = 5076
Step 7: 5076 + 846 = 5922
Step 8: 5922 + 846 = 6768
Step 9: 6768 + 846 = 7614
Step 10: 7614 + 846 = 8460
Step 11: 8460 + 846 = 9306
Step 12: 9306 + 846 = 10152
Step 13: 10152 + 846 = 10998
Step 14: 10998 + 846 = 11844
Step 15: 11844 + 846 = 12690
Step 16: 12690 + 846 = 13536
Step 17: 13536 + 846 = 14382
Step 18: 14382 + 846 = 15228
Step 19: 15228 + 846 = 16074
Step 20: 16074 + 846 = 16920
Step 21: 16920 + 846 = 17766
Step 22: 17766 + 846 = 18612
Step 23: 18612 + 846 = 19458
Step 24: 19458 + 846 = 20304
Step 25: 20304 + 846 = 21150
Step 26: 21150 + 846 = 21996
Step 27: 21996 + 846 = 22842
Step 28: 22842 + 846 = 23688
Step 29: 23688 + 846 = 24534
Step 30: 24534 + 846 = 25380
Step 31: 25380 + 846 = 26226
Step 32: 26226 + 846 = 27072
Step 33: 27072 + 846 = 27918
Step 34: 27918 + 846 = 28764
Step 35: 28764 + 846 = 29610
Step 36: 29610 + 846 = 30456
Step 37: 30456 + 846 = 31302
Step 38: 31302 + 846 = 32148
Step 39: 32148 + 846 = 32994
Step 40: 32994 + 846 = 33840
Step 41: 33840 + 846 = 34686
Step 42: 34686 + 846 = 35532
Step 43: 35532 + 846 = 36378
Step 44: 36378 + 846 = 37224
Step 45: 37224 + 846 = 38070
Step 46: 38070 + 846 = 38916
Step 47: 38916 + 846 = 39762
Step 48: 39762 + 846 = 40608
Step 49: 40608 + 846 = 41454
Step 50: 41454 + 846 = 42300
Step 51: 42300 + 846 = 43146
Step 52: 43146 + 846 = 43992
Step 53: 43992 + 846 = 44838
Step 54: 44838 + 846 = 45684
Step 55: 45684 + 846 = 46530
Step 56: 46530 + 846 = 47376
Step 57: 47376 + 846 = 48222
Step 58: 48222 + 846 = 49068
Step 59: 49068 + 846 = 49914
Step 60: 49914 + 846 = 50760
Step 61: 50760 + 846 = 51606
Step 62: 51606 + 846 = 52452
Step 63: 52452 + 846 = 53298
Step 64: 53298 + 846 = 54144
Step 65: 54144 + 846 = 54990
Step 66: 54990 + 846 = 55836
Step 67: 55836 + 846 = 56682
Step 68: 56682 + 846 = 57528
Step 69: 57528 + 846 = 58374
Step 70: 58374 + 846 = 59220
Step 71: 59220 + 846 = 60066
Step 72: 60066 + 846 = 60912
Step 73: 60912 + 846 = 61758
Step 74: 61758 + 846 = 62604
Step 75: 62604 + 846 = 63450

So, 846*75 = 63450