OK, let's work through this together. We're starting with 225 and we're going to multiply it by 66, which means we add 225 to itself 66 times.
Step 1: 0 + 225 = 225
Step 2: 225 + 225 = 450
Step 3: 450 + 225 = 675
Step 4: 675 + 225 = 900
Step 5: 900 + 225 = 1125
Step 6: 1125 + 225 = 1350
Step 7: 1350 + 225 = 1575
Step 8: 1575 + 225 = 1800
Step 9: 1800 + 225 = 2025
Step 10: 2025 + 225 = 2250
Step 11: 2250 + 225 = 2475
Step 12: 2475 + 225 = 2700
Step 13: 2700 + 225 = 2925
Step 14: 2925 + 225 = 3150
Step 15: 3150 + 225 = 3375
Step 16: 3375 + 225 = 3600
Step 17: 3600 + 225 = 3825
Step 18: 3825 + 225 = 4050
Step 19: 4050 + 225 = 4275
Step 20: 4275 + 225 = 4500
Step 21: 4500 + 225 = 4725
Step 22: 4725 + 225 = 4950
Step 23: 4950 + 225 = 5175
Step 24: 5175 + 225 = 5400
Step 25: 5400 + 225 = 5625
Step 26: 5625 + 225 = 5850
Step 27: 5850 + 225 = 6075
Step 28: 6075 + 225 = 6300
Step 29: 6300 + 225 = 6525
Step 30: 6525 + 225 = 6750
Step 31: 6750 + 225 = 6975
Step 32: 6975 + 225 = 7200
Step 33: 7200 + 225 = 7425
Step 34: 7425 + 225 = 7650
Step 35: 7650 + 225 = 7875
Step 36: 7875 + 225 = 8100
Step 37: 8100 + 225 = 8325
Step 38: 8325 + 225 = 8550
Step 39: 8550 + 225 = 8775
Step 40: 8775 + 225 = 9000
Step 41: 9000 + 225 = 9225
Step 42: 9225 + 225 = 9450
Step 43: 9450 + 225 = 9675
Step 44: 9675 + 225 = 9900
Step 45: 9900 + 225 = 10125
Step 46: 10125 + 225 = 10350
Step 47: 10350 + 225 = 10575
Step 48: 10575 + 225 = 10800
Step 49: 10800 + 225 = 11025
Step 50: 11025 + 225 = 11250
Step 51: 11250 + 225 = 11475
Step 52: 11475 + 225 = 11700
Step 53: 11700 + 225 = 11925
Step 54: 11925 + 225 = 12150
Step 55: 12150 + 225 = 12375
Step 56: 12375 + 225 = 12600
Step 57: 12600 + 225 = 12825
Step 58: 12825 + 225 = 13050
Step 59: 13050 + 225 = 13275
Step 60: 13275 + 225 = 13500
Step 61: 13500 + 225 = 13725
Step 62: 13725 + 225 = 13950
Step 63: 13950 + 225 = 14175
Step 64: 14175 + 225 = 14400
Step 65: 14400 + 225 = 14625
Step 66: 14625 + 225 = 14850

So, 225*66 = 14850