Let's roll up our sleeves and solve this. We have 450 and we're going to multiply it by 9, essentially adding 450 to itself 9 times.
Step 1: 0 + 450 = 450
Step 2: 450 + 450 = 900
Step 3: 900 + 450 = 1350
Step 4: 1350 + 450 = 1800
Step 5: 1800 + 450 = 2250
Step 6: 2250 + 450 = 2700
Step 7: 2700 + 450 = 3150
Step 8: 3150 + 450 = 3600
Step 9: 3600 + 450 = 4050

So, 450*9 = 4050