Alright, let's solve this math problem step by step. First, we have the number 125. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 13. So, we're going to take the number 125 and add it to itself 13 times.
Step 1: 0 + 125 = 125
Step 2: 125 + 125 = 250
Step 3: 250 + 125 = 375
Step 4: 375 + 125 = 500
Step 5: 500 + 125 = 625
Step 6: 625 + 125 = 750
Step 7: 750 + 125 = 875
Step 8: 875 + 125 = 1000
Step 9: 1000 + 125 = 1125
Step 10: 1125 + 125 = 1250
Step 11: 1250 + 125 = 1375
Step 12: 1375 + 125 = 1500
Step 13: 1500 + 125 = 1625

So, 125*13 = 1625