OK, let's crack this. We're given 102 and our task is to multiply it by 43. Essentially, we'll be adding 102 to itself 43 times.
Step 1: 0 + 102 = 102
Step 2: 102 + 102 = 204
Step 3: 204 + 102 = 306
Step 4: 306 + 102 = 408
Step 5: 408 + 102 = 510
Step 6: 510 + 102 = 612
Step 7: 612 + 102 = 714
Step 8: 714 + 102 = 816
Step 9: 816 + 102 = 918
Step 10: 918 + 102 = 1020
Step 11: 1020 + 102 = 1122
Step 12: 1122 + 102 = 1224
Step 13: 1224 + 102 = 1326
Step 14: 1326 + 102 = 1428
Step 15: 1428 + 102 = 1530
Step 16: 1530 + 102 = 1632
Step 17: 1632 + 102 = 1734
Step 18: 1734 + 102 = 1836
Step 19: 1836 + 102 = 1938
Step 20: 1938 + 102 = 2040
Step 21: 2040 + 102 = 2142
Step 22: 2142 + 102 = 2244
Step 23: 2244 + 102 = 2346
Step 24: 2346 + 102 = 2448
Step 25: 2448 + 102 = 2550
Step 26: 2550 + 102 = 2652
Step 27: 2652 + 102 = 2754
Step 28: 2754 + 102 = 2856
Step 29: 2856 + 102 = 2958
Step 30: 2958 + 102 = 3060
Step 31: 3060 + 102 = 3162
Step 32: 3162 + 102 = 3264
Step 33: 3264 + 102 = 3366
Step 34: 3366 + 102 = 3468
Step 35: 3468 + 102 = 3570
Step 36: 3570 + 102 = 3672
Step 37: 3672 + 102 = 3774
Step 38: 3774 + 102 = 3876
Step 39: 3876 + 102 = 3978
Step 40: 3978 + 102 = 4080
Step 41: 4080 + 102 = 4182
Step 42: 4182 + 102 = 4284
Step 43: 4284 + 102 = 4386

So, 102*43 = 4386