Without delay, let's solve this. We've got 999 and we will be multiplying it by 5, that is, adding 999 to itself 5 times.
Step 1: 0 + 999 = 999
Step 2: 999 + 999 = 1998
Step 3: 1998 + 999 = 2997
Step 4: 2997 + 999 = 3996
Step 5: 3996 + 999 = 4995

So, 999*5 = 4995