Let's get this math done. We have 225 and we're going to multiply it by 5. This is the same as taking 225 and adding it to itself 5 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

So, 225*5 = 1125