Sure thing, let's get straight to it. We start with 654 and we're going to multiply it by 42, which means adding 654 to itself 42 times.
Step 1: 0 + 654 = 654
Step 2: 654 + 654 = 1308
Step 3: 1308 + 654 = 1962
Step 4: 1962 + 654 = 2616
Step 5: 2616 + 654 = 3270
Step 6: 3270 + 654 = 3924
Step 7: 3924 + 654 = 4578
Step 8: 4578 + 654 = 5232
Step 9: 5232 + 654 = 5886
Step 10: 5886 + 654 = 6540
Step 11: 6540 + 654 = 7194
Step 12: 7194 + 654 = 7848
Step 13: 7848 + 654 = 8502
Step 14: 8502 + 654 = 9156
Step 15: 9156 + 654 = 9810
Step 16: 9810 + 654 = 10464
Step 17: 10464 + 654 = 11118
Step 18: 11118 + 654 = 11772
Step 19: 11772 + 654 = 12426
Step 20: 12426 + 654 = 13080
Step 21: 13080 + 654 = 13734
Step 22: 13734 + 654 = 14388
Step 23: 14388 + 654 = 15042
Step 24: 15042 + 654 = 15696
Step 25: 15696 + 654 = 16350
Step 26: 16350 + 654 = 17004
Step 27: 17004 + 654 = 17658
Step 28: 17658 + 654 = 18312
Step 29: 18312 + 654 = 18966
Step 30: 18966 + 654 = 19620
Step 31: 19620 + 654 = 20274
Step 32: 20274 + 654 = 20928
Step 33: 20928 + 654 = 21582
Step 34: 21582 + 654 = 22236
Step 35: 22236 + 654 = 22890
Step 36: 22890 + 654 = 23544
Step 37: 23544 + 654 = 24198
Step 38: 24198 + 654 = 24852
Step 39: 24852 + 654 = 25506
Step 40: 25506 + 654 = 26160
Step 41: 26160 + 654 = 26814
Step 42: 26814 + 654 = 27468

So, 654*42 = 27468