Without delay, let's solve this. We've got 600 and we will be multiplying it by 126, that is, adding 600 to itself 126 times.
Step 1: 0 + 600 = 600
Step 2: 600 + 600 = 1200
Step 3: 1200 + 600 = 1800
Step 4: 1800 + 600 = 2400
Step 5: 2400 + 600 = 3000
Step 6: 3000 + 600 = 3600
Step 7: 3600 + 600 = 4200
Step 8: 4200 + 600 = 4800
Step 9: 4800 + 600 = 5400
Step 10: 5400 + 600 = 6000
Step 11: 6000 + 600 = 6600
Step 12: 6600 + 600 = 7200
Step 13: 7200 + 600 = 7800
Step 14: 7800 + 600 = 8400
Step 15: 8400 + 600 = 9000
Step 16: 9000 + 600 = 9600
Step 17: 9600 + 600 = 10200
Step 18: 10200 + 600 = 10800
Step 19: 10800 + 600 = 11400
Step 20: 11400 + 600 = 12000
Step 21: 12000 + 600 = 12600
Step 22: 12600 + 600 = 13200
Step 23: 13200 + 600 = 13800
Step 24: 13800 + 600 = 14400
Step 25: 14400 + 600 = 15000
Step 26: 15000 + 600 = 15600
Step 27: 15600 + 600 = 16200
Step 28: 16200 + 600 = 16800
Step 29: 16800 + 600 = 17400
Step 30: 17400 + 600 = 18000
Step 31: 18000 + 600 = 18600
Step 32: 18600 + 600 = 19200
Step 33: 19200 + 600 = 19800
Step 34: 19800 + 600 = 20400
Step 35: 20400 + 600 = 21000
Step 36: 21000 + 600 = 21600
Step 37: 21600 + 600 = 22200
Step 38: 22200 + 600 = 22800
Step 39: 22800 + 600 = 23400
Step 40: 23400 + 600 = 24000
Step 41: 24000 + 600 = 24600
Step 42: 24600 + 600 = 25200
Step 43: 25200 + 600 = 25800
Step 44: 25800 + 600 = 26400
Step 45: 26400 + 600 = 27000
Step 46: 27000 + 600 = 27600
Step 47: 27600 + 600 = 28200
Step 48: 28200 + 600 = 28800
Step 49: 28800 + 600 = 29400
Step 50: 29400 + 600 = 30000
Step 51: 30000 + 600 = 30600
Step 52: 30600 + 600 = 31200
Step 53: 31200 + 600 = 31800
Step 54: 31800 + 600 = 32400
Step 55: 32400 + 600 = 33000
Step 56: 33000 + 600 = 33600
Step 57: 33600 + 600 = 34200
Step 58: 34200 + 600 = 34800
Step 59: 34800 + 600 = 35400
Step 60: 35400 + 600 = 36000
Step 61: 36000 + 600 = 36600
Step 62: 36600 + 600 = 37200
Step 63: 37200 + 600 = 37800
Step 64: 37800 + 600 = 38400
Step 65: 38400 + 600 = 39000
Step 66: 39000 + 600 = 39600
Step 67: 39600 + 600 = 40200
Step 68: 40200 + 600 = 40800
Step 69: 40800 + 600 = 41400
Step 70: 41400 + 600 = 42000
Step 71: 42000 + 600 = 42600
Step 72: 42600 + 600 = 43200
Step 73: 43200 + 600 = 43800
Step 74: 43800 + 600 = 44400
Step 75: 44400 + 600 = 45000
Step 76: 45000 + 600 = 45600
Step 77: 45600 + 600 = 46200
Step 78: 46200 + 600 = 46800
Step 79: 46800 + 600 = 47400
Step 80: 47400 + 600 = 48000
Step 81: 48000 + 600 = 48600
Step 82: 48600 + 600 = 49200
Step 83: 49200 + 600 = 49800
Step 84: 49800 + 600 = 50400
Step 85: 50400 + 600 = 51000
Step 86: 51000 + 600 = 51600
Step 87: 51600 + 600 = 52200
Step 88: 52200 + 600 = 52800
Step 89: 52800 + 600 = 53400
Step 90: 53400 + 600 = 54000
Step 91: 54000 + 600 = 54600
Step 92: 54600 + 600 = 55200
Step 93: 55200 + 600 = 55800
Step 94: 55800 + 600 = 56400
Step 95: 56400 + 600 = 57000
Step 96: 57000 + 600 = 57600
Step 97: 57600 + 600 = 58200
Step 98: 58200 + 600 = 58800
Step 99: 58800 + 600 = 59400
Step 100: 59400 + 600 = 60000
Step 101: 60000 + 600 = 60600
Step 102: 60600 + 600 = 61200
Step 103: 61200 + 600 = 61800
Step 104: 61800 + 600 = 62400
Step 105: 62400 + 600 = 63000
Step 106: 63000 + 600 = 63600
Step 107: 63600 + 600 = 64200
Step 108: 64200 + 600 = 64800
Step 109: 64800 + 600 = 65400
Step 110: 65400 + 600 = 66000
Step 111: 66000 + 600 = 66600
Step 112: 66600 + 600 = 67200
Step 113: 67200 + 600 = 67800
Step 114: 67800 + 600 = 68400
Step 115: 68400 + 600 = 69000
Step 116: 69000 + 600 = 69600
Step 117: 69600 + 600 = 70200
Step 118: 70200 + 600 = 70800
Step 119: 70800 + 600 = 71400
Step 120: 71400 + 600 = 72000
Step 121: 72000 + 600 = 72600
Step 122: 72600 + 600 = 73200
Step 123: 73200 + 600 = 73800
Step 124: 73800 + 600 = 74400
Step 125: 74400 + 600 = 75000
Step 126: 75000 + 600 = 75600

So, 600*126 = 75600