Let's get this math done. We have 839 and we're going to multiply it by 5. This is the same as taking 839 and adding it to itself 5 times.
Step 1: 0 + 839 = 839
Step 2: 839 + 839 = 1678
Step 3: 1678 + 839 = 2517
Step 4: 2517 + 839 = 3356
Step 5: 3356 + 839 = 4195

So, 839*5 = 4195