Let's get this math done. We have 403 and we're going to multiply it by 10. This is the same as taking 403 and adding it to itself 10 times.
Step 1: 0 + 403 = 403
Step 2: 403 + 403 = 806
Step 3: 806 + 403 = 1209
Step 4: 1209 + 403 = 1612
Step 5: 1612 + 403 = 2015
Step 6: 2015 + 403 = 2418
Step 7: 2418 + 403 = 2821
Step 8: 2821 + 403 = 3224
Step 9: 3224 + 403 = 3627
Step 10: 3627 + 403 = 4030

So, 403*10 = 4030