Sure thing, let's get straight to it. We start with 455 and we're going to multiply it by 48, which means adding 455 to itself 48 times.
Step 1: 0 + 455 = 455
Step 2: 455 + 455 = 910
Step 3: 910 + 455 = 1365
Step 4: 1365 + 455 = 1820
Step 5: 1820 + 455 = 2275
Step 6: 2275 + 455 = 2730
Step 7: 2730 + 455 = 3185
Step 8: 3185 + 455 = 3640
Step 9: 3640 + 455 = 4095
Step 10: 4095 + 455 = 4550
Step 11: 4550 + 455 = 5005
Step 12: 5005 + 455 = 5460
Step 13: 5460 + 455 = 5915
Step 14: 5915 + 455 = 6370
Step 15: 6370 + 455 = 6825
Step 16: 6825 + 455 = 7280
Step 17: 7280 + 455 = 7735
Step 18: 7735 + 455 = 8190
Step 19: 8190 + 455 = 8645
Step 20: 8645 + 455 = 9100
Step 21: 9100 + 455 = 9555
Step 22: 9555 + 455 = 10010
Step 23: 10010 + 455 = 10465
Step 24: 10465 + 455 = 10920
Step 25: 10920 + 455 = 11375
Step 26: 11375 + 455 = 11830
Step 27: 11830 + 455 = 12285
Step 28: 12285 + 455 = 12740
Step 29: 12740 + 455 = 13195
Step 30: 13195 + 455 = 13650
Step 31: 13650 + 455 = 14105
Step 32: 14105 + 455 = 14560
Step 33: 14560 + 455 = 15015
Step 34: 15015 + 455 = 15470
Step 35: 15470 + 455 = 15925
Step 36: 15925 + 455 = 16380
Step 37: 16380 + 455 = 16835
Step 38: 16835 + 455 = 17290
Step 39: 17290 + 455 = 17745
Step 40: 17745 + 455 = 18200
Step 41: 18200 + 455 = 18655
Step 42: 18655 + 455 = 19110
Step 43: 19110 + 455 = 19565
Step 44: 19565 + 455 = 20020
Step 45: 20020 + 455 = 20475
Step 46: 20475 + 455 = 20930
Step 47: 20930 + 455 = 21385
Step 48: 21385 + 455 = 21840

So, 455*48 = 21840