OK, let's crack this. We're given 519 and our task is to multiply it by 78. Essentially, we'll be adding 519 to itself 78 times.
Step 1: 0 + 519 = 519
Step 2: 519 + 519 = 1038
Step 3: 1038 + 519 = 1557
Step 4: 1557 + 519 = 2076
Step 5: 2076 + 519 = 2595
Step 6: 2595 + 519 = 3114
Step 7: 3114 + 519 = 3633
Step 8: 3633 + 519 = 4152
Step 9: 4152 + 519 = 4671
Step 10: 4671 + 519 = 5190
Step 11: 5190 + 519 = 5709
Step 12: 5709 + 519 = 6228
Step 13: 6228 + 519 = 6747
Step 14: 6747 + 519 = 7266
Step 15: 7266 + 519 = 7785
Step 16: 7785 + 519 = 8304
Step 17: 8304 + 519 = 8823
Step 18: 8823 + 519 = 9342
Step 19: 9342 + 519 = 9861
Step 20: 9861 + 519 = 10380
Step 21: 10380 + 519 = 10899
Step 22: 10899 + 519 = 11418
Step 23: 11418 + 519 = 11937
Step 24: 11937 + 519 = 12456
Step 25: 12456 + 519 = 12975
Step 26: 12975 + 519 = 13494
Step 27: 13494 + 519 = 14013
Step 28: 14013 + 519 = 14532
Step 29: 14532 + 519 = 15051
Step 30: 15051 + 519 = 15570
Step 31: 15570 + 519 = 16089
Step 32: 16089 + 519 = 16608
Step 33: 16608 + 519 = 17127
Step 34: 17127 + 519 = 17646
Step 35: 17646 + 519 = 18165
Step 36: 18165 + 519 = 18684
Step 37: 18684 + 519 = 19203
Step 38: 19203 + 519 = 19722
Step 39: 19722 + 519 = 20241
Step 40: 20241 + 519 = 20760
Step 41: 20760 + 519 = 21279
Step 42: 21279 + 519 = 21798
Step 43: 21798 + 519 = 22317
Step 44: 22317 + 519 = 22836
Step 45: 22836 + 519 = 23355
Step 46: 23355 + 519 = 23874
Step 47: 23874 + 519 = 24393
Step 48: 24393 + 519 = 24912
Step 49: 24912 + 519 = 25431
Step 50: 25431 + 519 = 25950
Step 51: 25950 + 519 = 26469
Step 52: 26469 + 519 = 26988
Step 53: 26988 + 519 = 27507
Step 54: 27507 + 519 = 28026
Step 55: 28026 + 519 = 28545
Step 56: 28545 + 519 = 29064
Step 57: 29064 + 519 = 29583
Step 58: 29583 + 519 = 30102
Step 59: 30102 + 519 = 30621
Step 60: 30621 + 519 = 31140
Step 61: 31140 + 519 = 31659
Step 62: 31659 + 519 = 32178
Step 63: 32178 + 519 = 32697
Step 64: 32697 + 519 = 33216
Step 65: 33216 + 519 = 33735
Step 66: 33735 + 519 = 34254
Step 67: 34254 + 519 = 34773
Step 68: 34773 + 519 = 35292
Step 69: 35292 + 519 = 35811
Step 70: 35811 + 519 = 36330
Step 71: 36330 + 519 = 36849
Step 72: 36849 + 519 = 37368
Step 73: 37368 + 519 = 37887
Step 74: 37887 + 519 = 38406
Step 75: 38406 + 519 = 38925
Step 76: 38925 + 519 = 39444
Step 77: 39444 + 519 = 39963
Step 78: 39963 + 519 = 40482

So, 519*78 = 40482