OK, let's crack this. We're given 387 and our task is to multiply it by 48. Essentially, we'll be adding 387 to itself 48 times.
Step 1: 0 + 387 = 387
Step 2: 387 + 387 = 774
Step 3: 774 + 387 = 1161
Step 4: 1161 + 387 = 1548
Step 5: 1548 + 387 = 1935
Step 6: 1935 + 387 = 2322
Step 7: 2322 + 387 = 2709
Step 8: 2709 + 387 = 3096
Step 9: 3096 + 387 = 3483
Step 10: 3483 + 387 = 3870
Step 11: 3870 + 387 = 4257
Step 12: 4257 + 387 = 4644
Step 13: 4644 + 387 = 5031
Step 14: 5031 + 387 = 5418
Step 15: 5418 + 387 = 5805
Step 16: 5805 + 387 = 6192
Step 17: 6192 + 387 = 6579
Step 18: 6579 + 387 = 6966
Step 19: 6966 + 387 = 7353
Step 20: 7353 + 387 = 7740
Step 21: 7740 + 387 = 8127
Step 22: 8127 + 387 = 8514
Step 23: 8514 + 387 = 8901
Step 24: 8901 + 387 = 9288
Step 25: 9288 + 387 = 9675
Step 26: 9675 + 387 = 10062
Step 27: 10062 + 387 = 10449
Step 28: 10449 + 387 = 10836
Step 29: 10836 + 387 = 11223
Step 30: 11223 + 387 = 11610
Step 31: 11610 + 387 = 11997
Step 32: 11997 + 387 = 12384
Step 33: 12384 + 387 = 12771
Step 34: 12771 + 387 = 13158
Step 35: 13158 + 387 = 13545
Step 36: 13545 + 387 = 13932
Step 37: 13932 + 387 = 14319
Step 38: 14319 + 387 = 14706
Step 39: 14706 + 387 = 15093
Step 40: 15093 + 387 = 15480
Step 41: 15480 + 387 = 15867
Step 42: 15867 + 387 = 16254
Step 43: 16254 + 387 = 16641
Step 44: 16641 + 387 = 17028
Step 45: 17028 + 387 = 17415
Step 46: 17415 + 387 = 17802
Step 47: 17802 + 387 = 18189
Step 48: 18189 + 387 = 18576

So, 387*48 = 18576