Alright, let's solve this math problem step by step. First, we have the number 807. 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 807 and add it to itself 20 times.
Step 1: 0 + 807 = 807
Step 2: 807 + 807 = 1614
Step 3: 1614 + 807 = 2421
Step 4: 2421 + 807 = 3228
Step 5: 3228 + 807 = 4035
Step 6: 4035 + 807 = 4842
Step 7: 4842 + 807 = 5649
Step 8: 5649 + 807 = 6456
Step 9: 6456 + 807 = 7263
Step 10: 7263 + 807 = 8070
Step 11: 8070 + 807 = 8877
Step 12: 8877 + 807 = 9684
Step 13: 9684 + 807 = 10491
Step 14: 10491 + 807 = 11298
Step 15: 11298 + 807 = 12105
Step 16: 12105 + 807 = 12912
Step 17: 12912 + 807 = 13719
Step 18: 13719 + 807 = 14526
Step 19: 14526 + 807 = 15333
Step 20: 15333 + 807 = 16140

So, 807*20 = 16140