Alright, let's solve this math problem step by step. First, we have the number 409. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 25. So, we're going to take the number 409 and add it to itself 25 times.
Step 1: 0 + 409 = 409
Step 2: 409 + 409 = 818
Step 3: 818 + 409 = 1227
Step 4: 1227 + 409 = 1636
Step 5: 1636 + 409 = 2045
Step 6: 2045 + 409 = 2454
Step 7: 2454 + 409 = 2863
Step 8: 2863 + 409 = 3272
Step 9: 3272 + 409 = 3681
Step 10: 3681 + 409 = 4090
Step 11: 4090 + 409 = 4499
Step 12: 4499 + 409 = 4908
Step 13: 4908 + 409 = 5317
Step 14: 5317 + 409 = 5726
Step 15: 5726 + 409 = 6135
Step 16: 6135 + 409 = 6544
Step 17: 6544 + 409 = 6953
Step 18: 6953 + 409 = 7362
Step 19: 7362 + 409 = 7771
Step 20: 7771 + 409 = 8180
Step 21: 8180 + 409 = 8589
Step 22: 8589 + 409 = 8998
Step 23: 8998 + 409 = 9407
Step 24: 9407 + 409 = 9816
Step 25: 9816 + 409 = 10225

So, 409*25 = 10225