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 10. So, we're going to take the number 125 and add it to itself 10 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

So, 125*10 = 1250