Let's roll up our sleeves and solve this. We have 281 and we're going to multiply it by 15, essentially adding 281 to itself 15 times.
Step 1: 0 + 281 = 281
Step 2: 281 + 281 = 562
Step 3: 562 + 281 = 843
Step 4: 843 + 281 = 1124
Step 5: 1124 + 281 = 1405
Step 6: 1405 + 281 = 1686
Step 7: 1686 + 281 = 1967
Step 8: 1967 + 281 = 2248
Step 9: 2248 + 281 = 2529
Step 10: 2529 + 281 = 2810
Step 11: 2810 + 281 = 3091
Step 12: 3091 + 281 = 3372
Step 13: 3372 + 281 = 3653
Step 14: 3653 + 281 = 3934
Step 15: 3934 + 281 = 4215

So, 281*15 = 4215