Alright, let's solve this math problem step by step. First, we have the number 681. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 31. So, we're going to take the number 681 and add it to itself 31 times.
Step 1: 0 + 681 = 681
Step 2: 681 + 681 = 1362
Step 3: 1362 + 681 = 2043
Step 4: 2043 + 681 = 2724
Step 5: 2724 + 681 = 3405
Step 6: 3405 + 681 = 4086
Step 7: 4086 + 681 = 4767
Step 8: 4767 + 681 = 5448
Step 9: 5448 + 681 = 6129
Step 10: 6129 + 681 = 6810
Step 11: 6810 + 681 = 7491
Step 12: 7491 + 681 = 8172
Step 13: 8172 + 681 = 8853
Step 14: 8853 + 681 = 9534
Step 15: 9534 + 681 = 10215
Step 16: 10215 + 681 = 10896
Step 17: 10896 + 681 = 11577
Step 18: 11577 + 681 = 12258
Step 19: 12258 + 681 = 12939
Step 20: 12939 + 681 = 13620
Step 21: 13620 + 681 = 14301
Step 22: 14301 + 681 = 14982
Step 23: 14982 + 681 = 15663
Step 24: 15663 + 681 = 16344
Step 25: 16344 + 681 = 17025
Step 26: 17025 + 681 = 17706
Step 27: 17706 + 681 = 18387
Step 28: 18387 + 681 = 19068
Step 29: 19068 + 681 = 19749
Step 30: 19749 + 681 = 20430
Step 31: 20430 + 681 = 21111

So, 681*31 = 21111