Let's get this math done. We have 350 and we're going to multiply it by 123. This is the same as taking 350 and adding it to itself 123 times.
Step 1: 0 + 350 = 350
Step 2: 350 + 350 = 700
Step 3: 700 + 350 = 1050
Step 4: 1050 + 350 = 1400
Step 5: 1400 + 350 = 1750
Step 6: 1750 + 350 = 2100
Step 7: 2100 + 350 = 2450
Step 8: 2450 + 350 = 2800
Step 9: 2800 + 350 = 3150
Step 10: 3150 + 350 = 3500
Step 11: 3500 + 350 = 3850
Step 12: 3850 + 350 = 4200
Step 13: 4200 + 350 = 4550
Step 14: 4550 + 350 = 4900
Step 15: 4900 + 350 = 5250
Step 16: 5250 + 350 = 5600
Step 17: 5600 + 350 = 5950
Step 18: 5950 + 350 = 6300
Step 19: 6300 + 350 = 6650
Step 20: 6650 + 350 = 7000
Step 21: 7000 + 350 = 7350
Step 22: 7350 + 350 = 7700
Step 23: 7700 + 350 = 8050
Step 24: 8050 + 350 = 8400
Step 25: 8400 + 350 = 8750
Step 26: 8750 + 350 = 9100
Step 27: 9100 + 350 = 9450
Step 28: 9450 + 350 = 9800
Step 29: 9800 + 350 = 10150
Step 30: 10150 + 350 = 10500
Step 31: 10500 + 350 = 10850
Step 32: 10850 + 350 = 11200
Step 33: 11200 + 350 = 11550
Step 34: 11550 + 350 = 11900
Step 35: 11900 + 350 = 12250
Step 36: 12250 + 350 = 12600
Step 37: 12600 + 350 = 12950
Step 38: 12950 + 350 = 13300
Step 39: 13300 + 350 = 13650
Step 40: 13650 + 350 = 14000
Step 41: 14000 + 350 = 14350
Step 42: 14350 + 350 = 14700
Step 43: 14700 + 350 = 15050
Step 44: 15050 + 350 = 15400
Step 45: 15400 + 350 = 15750
Step 46: 15750 + 350 = 16100
Step 47: 16100 + 350 = 16450
Step 48: 16450 + 350 = 16800
Step 49: 16800 + 350 = 17150
Step 50: 17150 + 350 = 17500
Step 51: 17500 + 350 = 17850
Step 52: 17850 + 350 = 18200
Step 53: 18200 + 350 = 18550
Step 54: 18550 + 350 = 18900
Step 55: 18900 + 350 = 19250
Step 56: 19250 + 350 = 19600
Step 57: 19600 + 350 = 19950
Step 58: 19950 + 350 = 20300
Step 59: 20300 + 350 = 20650
Step 60: 20650 + 350 = 21000
Step 61: 21000 + 350 = 21350
Step 62: 21350 + 350 = 21700
Step 63: 21700 + 350 = 22050
Step 64: 22050 + 350 = 22400
Step 65: 22400 + 350 = 22750
Step 66: 22750 + 350 = 23100
Step 67: 23100 + 350 = 23450
Step 68: 23450 + 350 = 23800
Step 69: 23800 + 350 = 24150
Step 70: 24150 + 350 = 24500
Step 71: 24500 + 350 = 24850
Step 72: 24850 + 350 = 25200
Step 73: 25200 + 350 = 25550
Step 74: 25550 + 350 = 25900
Step 75: 25900 + 350 = 26250
Step 76: 26250 + 350 = 26600
Step 77: 26600 + 350 = 26950
Step 78: 26950 + 350 = 27300
Step 79: 27300 + 350 = 27650
Step 80: 27650 + 350 = 28000
Step 81: 28000 + 350 = 28350
Step 82: 28350 + 350 = 28700
Step 83: 28700 + 350 = 29050
Step 84: 29050 + 350 = 29400
Step 85: 29400 + 350 = 29750
Step 86: 29750 + 350 = 30100
Step 87: 30100 + 350 = 30450
Step 88: 30450 + 350 = 30800
Step 89: 30800 + 350 = 31150
Step 90: 31150 + 350 = 31500
Step 91: 31500 + 350 = 31850
Step 92: 31850 + 350 = 32200
Step 93: 32200 + 350 = 32550
Step 94: 32550 + 350 = 32900
Step 95: 32900 + 350 = 33250
Step 96: 33250 + 350 = 33600
Step 97: 33600 + 350 = 33950
Step 98: 33950 + 350 = 34300
Step 99: 34300 + 350 = 34650
Step 100: 34650 + 350 = 35000
Step 101: 35000 + 350 = 35350
Step 102: 35350 + 350 = 35700
Step 103: 35700 + 350 = 36050
Step 104: 36050 + 350 = 36400
Step 105: 36400 + 350 = 36750
Step 106: 36750 + 350 = 37100
Step 107: 37100 + 350 = 37450
Step 108: 37450 + 350 = 37800
Step 109: 37800 + 350 = 38150
Step 110: 38150 + 350 = 38500
Step 111: 38500 + 350 = 38850
Step 112: 38850 + 350 = 39200
Step 113: 39200 + 350 = 39550
Step 114: 39550 + 350 = 39900
Step 115: 39900 + 350 = 40250
Step 116: 40250 + 350 = 40600
Step 117: 40600 + 350 = 40950
Step 118: 40950 + 350 = 41300
Step 119: 41300 + 350 = 41650
Step 120: 41650 + 350 = 42000
Step 121: 42000 + 350 = 42350
Step 122: 42350 + 350 = 42700
Step 123: 42700 + 350 = 43050

So, 350*123 = 43050