Sure thing, let's get straight to it. We start with 877 and we're going to multiply it by 13, which means adding 877 to itself 13 times.
Step 1: 0 + 877 = 877
Step 2: 877 + 877 = 1754
Step 3: 1754 + 877 = 2631
Step 4: 2631 + 877 = 3508
Step 5: 3508 + 877 = 4385
Step 6: 4385 + 877 = 5262
Step 7: 5262 + 877 = 6139
Step 8: 6139 + 877 = 7016
Step 9: 7016 + 877 = 7893
Step 10: 7893 + 877 = 8770
Step 11: 8770 + 877 = 9647
Step 12: 9647 + 877 = 10524
Step 13: 10524 + 877 = 11401

So, 877*13 = 11401