Without delay, let's solve this. We've got 829 and we will be multiplying it by 25, that is, adding 829 to itself 25 times.
Step 1: 0 + 829 = 829
Step 2: 829 + 829 = 1658
Step 3: 1658 + 829 = 2487
Step 4: 2487 + 829 = 3316
Step 5: 3316 + 829 = 4145
Step 6: 4145 + 829 = 4974
Step 7: 4974 + 829 = 5803
Step 8: 5803 + 829 = 6632
Step 9: 6632 + 829 = 7461
Step 10: 7461 + 829 = 8290
Step 11: 8290 + 829 = 9119
Step 12: 9119 + 829 = 9948
Step 13: 9948 + 829 = 10777
Step 14: 10777 + 829 = 11606
Step 15: 11606 + 829 = 12435
Step 16: 12435 + 829 = 13264
Step 17: 13264 + 829 = 14093
Step 18: 14093 + 829 = 14922
Step 19: 14922 + 829 = 15751
Step 20: 15751 + 829 = 16580
Step 21: 16580 + 829 = 17409
Step 22: 17409 + 829 = 18238
Step 23: 18238 + 829 = 19067
Step 24: 19067 + 829 = 19896
Step 25: 19896 + 829 = 20725

So, 829*25 = 20725