OK, let's crack this. We're given 874 and our task is to multiply it by 42. Essentially, we'll be adding 874 to itself 42 times.
Step 1: 0 + 874 = 874
Step 2: 874 + 874 = 1748
Step 3: 1748 + 874 = 2622
Step 4: 2622 + 874 = 3496
Step 5: 3496 + 874 = 4370
Step 6: 4370 + 874 = 5244
Step 7: 5244 + 874 = 6118
Step 8: 6118 + 874 = 6992
Step 9: 6992 + 874 = 7866
Step 10: 7866 + 874 = 8740
Step 11: 8740 + 874 = 9614
Step 12: 9614 + 874 = 10488
Step 13: 10488 + 874 = 11362
Step 14: 11362 + 874 = 12236
Step 15: 12236 + 874 = 13110
Step 16: 13110 + 874 = 13984
Step 17: 13984 + 874 = 14858
Step 18: 14858 + 874 = 15732
Step 19: 15732 + 874 = 16606
Step 20: 16606 + 874 = 17480
Step 21: 17480 + 874 = 18354
Step 22: 18354 + 874 = 19228
Step 23: 19228 + 874 = 20102
Step 24: 20102 + 874 = 20976
Step 25: 20976 + 874 = 21850
Step 26: 21850 + 874 = 22724
Step 27: 22724 + 874 = 23598
Step 28: 23598 + 874 = 24472
Step 29: 24472 + 874 = 25346
Step 30: 25346 + 874 = 26220
Step 31: 26220 + 874 = 27094
Step 32: 27094 + 874 = 27968
Step 33: 27968 + 874 = 28842
Step 34: 28842 + 874 = 29716
Step 35: 29716 + 874 = 30590
Step 36: 30590 + 874 = 31464
Step 37: 31464 + 874 = 32338
Step 38: 32338 + 874 = 33212
Step 39: 33212 + 874 = 34086
Step 40: 34086 + 874 = 34960
Step 41: 34960 + 874 = 35834
Step 42: 35834 + 874 = 36708

So, 874*42 = 36708