Without delay, let's solve this. We've got 688 and we will be multiplying it by 39, that is, adding 688 to itself 39 times.
Step 1: 0 + 688 = 688
Step 2: 688 + 688 = 1376
Step 3: 1376 + 688 = 2064
Step 4: 2064 + 688 = 2752
Step 5: 2752 + 688 = 3440
Step 6: 3440 + 688 = 4128
Step 7: 4128 + 688 = 4816
Step 8: 4816 + 688 = 5504
Step 9: 5504 + 688 = 6192
Step 10: 6192 + 688 = 6880
Step 11: 6880 + 688 = 7568
Step 12: 7568 + 688 = 8256
Step 13: 8256 + 688 = 8944
Step 14: 8944 + 688 = 9632
Step 15: 9632 + 688 = 10320
Step 16: 10320 + 688 = 11008
Step 17: 11008 + 688 = 11696
Step 18: 11696 + 688 = 12384
Step 19: 12384 + 688 = 13072
Step 20: 13072 + 688 = 13760
Step 21: 13760 + 688 = 14448
Step 22: 14448 + 688 = 15136
Step 23: 15136 + 688 = 15824
Step 24: 15824 + 688 = 16512
Step 25: 16512 + 688 = 17200
Step 26: 17200 + 688 = 17888
Step 27: 17888 + 688 = 18576
Step 28: 18576 + 688 = 19264
Step 29: 19264 + 688 = 19952
Step 30: 19952 + 688 = 20640
Step 31: 20640 + 688 = 21328
Step 32: 21328 + 688 = 22016
Step 33: 22016 + 688 = 22704
Step 34: 22704 + 688 = 23392
Step 35: 23392 + 688 = 24080
Step 36: 24080 + 688 = 24768
Step 37: 24768 + 688 = 25456
Step 38: 25456 + 688 = 26144
Step 39: 26144 + 688 = 26832

So, 688*39 = 26832