Alright, let's solve this math problem step by step. First, we have the number 691. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 20. So, we're going to take the number 691 and add it to itself 20 times.
Step 1: 0 + 691 = 691
Step 2: 691 + 691 = 1382
Step 3: 1382 + 691 = 2073
Step 4: 2073 + 691 = 2764
Step 5: 2764 + 691 = 3455
Step 6: 3455 + 691 = 4146
Step 7: 4146 + 691 = 4837
Step 8: 4837 + 691 = 5528
Step 9: 5528 + 691 = 6219
Step 10: 6219 + 691 = 6910
Step 11: 6910 + 691 = 7601
Step 12: 7601 + 691 = 8292
Step 13: 8292 + 691 = 8983
Step 14: 8983 + 691 = 9674
Step 15: 9674 + 691 = 10365
Step 16: 10365 + 691 = 11056
Step 17: 11056 + 691 = 11747
Step 18: 11747 + 691 = 12438
Step 19: 12438 + 691 = 13129
Step 20: 13129 + 691 = 13820

So, 691*20 = 13820