Let's get this math done. We have 76 and we're going to multiply it by 21. This is the same as taking 76 and adding it to itself 21 times.
Step 1: 0 + 76 = 76
Step 2: 76 + 76 = 152
Step 3: 152 + 76 = 228
Step 4: 228 + 76 = 304
Step 5: 304 + 76 = 380
Step 6: 380 + 76 = 456
Step 7: 456 + 76 = 532
Step 8: 532 + 76 = 608
Step 9: 608 + 76 = 684
Step 10: 684 + 76 = 760
Step 11: 760 + 76 = 836
Step 12: 836 + 76 = 912
Step 13: 912 + 76 = 988
Step 14: 988 + 76 = 1064
Step 15: 1064 + 76 = 1140
Step 16: 1140 + 76 = 1216
Step 17: 1216 + 76 = 1292
Step 18: 1292 + 76 = 1368
Step 19: 1368 + 76 = 1444
Step 20: 1444 + 76 = 1520
Step 21: 1520 + 76 = 1596

So, 76*21 = 1596