Sure thing! We've got 931 and we're gonna multiply it by 13. That's the same as adding 931 to itself 13 times.
Step 1: 0 + 931 = 931
Step 2: 931 + 931 = 1862
Step 3: 1862 + 931 = 2793
Step 4: 2793 + 931 = 3724
Step 5: 3724 + 931 = 4655
Step 6: 4655 + 931 = 5586
Step 7: 5586 + 931 = 6517
Step 8: 6517 + 931 = 7448
Step 9: 7448 + 931 = 8379
Step 10: 8379 + 931 = 9310
Step 11: 9310 + 931 = 10241
Step 12: 10241 + 931 = 11172
Step 13: 11172 + 931 = 12103

So, 931*13 = 12103