Let's roll up our sleeves and solve this. We have 792 and we're going to multiply it by 51, essentially adding 792 to itself 51 times.
Step 1: 0 + 792 = 792
Step 2: 792 + 792 = 1584
Step 3: 1584 + 792 = 2376
Step 4: 2376 + 792 = 3168
Step 5: 3168 + 792 = 3960
Step 6: 3960 + 792 = 4752
Step 7: 4752 + 792 = 5544
Step 8: 5544 + 792 = 6336
Step 9: 6336 + 792 = 7128
Step 10: 7128 + 792 = 7920
Step 11: 7920 + 792 = 8712
Step 12: 8712 + 792 = 9504
Step 13: 9504 + 792 = 10296
Step 14: 10296 + 792 = 11088
Step 15: 11088 + 792 = 11880
Step 16: 11880 + 792 = 12672
Step 17: 12672 + 792 = 13464
Step 18: 13464 + 792 = 14256
Step 19: 14256 + 792 = 15048
Step 20: 15048 + 792 = 15840
Step 21: 15840 + 792 = 16632
Step 22: 16632 + 792 = 17424
Step 23: 17424 + 792 = 18216
Step 24: 18216 + 792 = 19008
Step 25: 19008 + 792 = 19800
Step 26: 19800 + 792 = 20592
Step 27: 20592 + 792 = 21384
Step 28: 21384 + 792 = 22176
Step 29: 22176 + 792 = 22968
Step 30: 22968 + 792 = 23760
Step 31: 23760 + 792 = 24552
Step 32: 24552 + 792 = 25344
Step 33: 25344 + 792 = 26136
Step 34: 26136 + 792 = 26928
Step 35: 26928 + 792 = 27720
Step 36: 27720 + 792 = 28512
Step 37: 28512 + 792 = 29304
Step 38: 29304 + 792 = 30096
Step 39: 30096 + 792 = 30888
Step 40: 30888 + 792 = 31680
Step 41: 31680 + 792 = 32472
Step 42: 32472 + 792 = 33264
Step 43: 33264 + 792 = 34056
Step 44: 34056 + 792 = 34848
Step 45: 34848 + 792 = 35640
Step 46: 35640 + 792 = 36432
Step 47: 36432 + 792 = 37224
Step 48: 37224 + 792 = 38016
Step 49: 38016 + 792 = 38808
Step 50: 38808 + 792 = 39600
Step 51: 39600 + 792 = 40392

So, 792*51 = 40392