Sure thing! We've got 211 and we're gonna multiply it by 21. That's the same as adding 211 to itself 21 times.
Step 1: 0 + 211 = 211
Step 2: 211 + 211 = 422
Step 3: 422 + 211 = 633
Step 4: 633 + 211 = 844
Step 5: 844 + 211 = 1055
Step 6: 1055 + 211 = 1266
Step 7: 1266 + 211 = 1477
Step 8: 1477 + 211 = 1688
Step 9: 1688 + 211 = 1899
Step 10: 1899 + 211 = 2110
Step 11: 2110 + 211 = 2321
Step 12: 2321 + 211 = 2532
Step 13: 2532 + 211 = 2743
Step 14: 2743 + 211 = 2954
Step 15: 2954 + 211 = 3165
Step 16: 3165 + 211 = 3376
Step 17: 3376 + 211 = 3587
Step 18: 3587 + 211 = 3798
Step 19: 3798 + 211 = 4009
Step 20: 4009 + 211 = 4220
Step 21: 4220 + 211 = 4431

So, 211*21 = 4431