Let's get this math done. We have 63 and we're going to multiply it by 25. This is the same as taking 63 and adding it to itself 25 times.
Step 1: 0 + 63 = 63
Step 2: 63 + 63 = 126
Step 3: 126 + 63 = 189
Step 4: 189 + 63 = 252
Step 5: 252 + 63 = 315
Step 6: 315 + 63 = 378
Step 7: 378 + 63 = 441
Step 8: 441 + 63 = 504
Step 9: 504 + 63 = 567
Step 10: 567 + 63 = 630
Step 11: 630 + 63 = 693
Step 12: 693 + 63 = 756
Step 13: 756 + 63 = 819
Step 14: 819 + 63 = 882
Step 15: 882 + 63 = 945
Step 16: 945 + 63 = 1008
Step 17: 1008 + 63 = 1071
Step 18: 1071 + 63 = 1134
Step 19: 1134 + 63 = 1197
Step 20: 1197 + 63 = 1260
Step 21: 1260 + 63 = 1323
Step 22: 1323 + 63 = 1386
Step 23: 1386 + 63 = 1449
Step 24: 1449 + 63 = 1512
Step 25: 1512 + 63 = 1575

So, 63*25 = 1575