Without delay, let's solve this. We've got 128 and we will be multiplying it by 42, that is, adding 128 to itself 42 times.
Step 1: 0 + 128 = 128
Step 2: 128 + 128 = 256
Step 3: 256 + 128 = 384
Step 4: 384 + 128 = 512
Step 5: 512 + 128 = 640
Step 6: 640 + 128 = 768
Step 7: 768 + 128 = 896
Step 8: 896 + 128 = 1024
Step 9: 1024 + 128 = 1152
Step 10: 1152 + 128 = 1280
Step 11: 1280 + 128 = 1408
Step 12: 1408 + 128 = 1536
Step 13: 1536 + 128 = 1664
Step 14: 1664 + 128 = 1792
Step 15: 1792 + 128 = 1920
Step 16: 1920 + 128 = 2048
Step 17: 2048 + 128 = 2176
Step 18: 2176 + 128 = 2304
Step 19: 2304 + 128 = 2432
Step 20: 2432 + 128 = 2560
Step 21: 2560 + 128 = 2688
Step 22: 2688 + 128 = 2816
Step 23: 2816 + 128 = 2944
Step 24: 2944 + 128 = 3072
Step 25: 3072 + 128 = 3200
Step 26: 3200 + 128 = 3328
Step 27: 3328 + 128 = 3456
Step 28: 3456 + 128 = 3584
Step 29: 3584 + 128 = 3712
Step 30: 3712 + 128 = 3840
Step 31: 3840 + 128 = 3968
Step 32: 3968 + 128 = 4096
Step 33: 4096 + 128 = 4224
Step 34: 4224 + 128 = 4352
Step 35: 4352 + 128 = 4480
Step 36: 4480 + 128 = 4608
Step 37: 4608 + 128 = 4736
Step 38: 4736 + 128 = 4864
Step 39: 4864 + 128 = 4992
Step 40: 4992 + 128 = 5120
Step 41: 5120 + 128 = 5248
Step 42: 5248 + 128 = 5376

So, 128*42 = 5376