Without delay, let's solve this. We've got 868 and we will be multiplying it by 15, that is, adding 868 to itself 15 times.
Step 1: 0 + 868 = 868
Step 2: 868 + 868 = 1736
Step 3: 1736 + 868 = 2604
Step 4: 2604 + 868 = 3472
Step 5: 3472 + 868 = 4340
Step 6: 4340 + 868 = 5208
Step 7: 5208 + 868 = 6076
Step 8: 6076 + 868 = 6944
Step 9: 6944 + 868 = 7812
Step 10: 7812 + 868 = 8680
Step 11: 8680 + 868 = 9548
Step 12: 9548 + 868 = 10416
Step 13: 10416 + 868 = 11284
Step 14: 11284 + 868 = 12152
Step 15: 12152 + 868 = 13020

So, 868*15 = 13020