Without delay, let's solve this. We've got 500 and we will be multiplying it by 20, that is, adding 500 to itself 20 times.
Step 1: 0 + 500 = 500
Step 2: 500 + 500 = 1000
Step 3: 1000 + 500 = 1500
Step 4: 1500 + 500 = 2000
Step 5: 2000 + 500 = 2500
Step 6: 2500 + 500 = 3000
Step 7: 3000 + 500 = 3500
Step 8: 3500 + 500 = 4000
Step 9: 4000 + 500 = 4500
Step 10: 4500 + 500 = 5000
Step 11: 5000 + 500 = 5500
Step 12: 5500 + 500 = 6000
Step 13: 6000 + 500 = 6500
Step 14: 6500 + 500 = 7000
Step 15: 7000 + 500 = 7500
Step 16: 7500 + 500 = 8000
Step 17: 8000 + 500 = 8500
Step 18: 8500 + 500 = 9000
Step 19: 9000 + 500 = 9500
Step 20: 9500 + 500 = 10000

So, 500*20 = 10000