OK, let's work through this together. We're starting with 225 and we're going to multiply it by 40, which means we add 225 to itself 40 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

So, 225*40 = 9000