Sure thing! We've got 561 and we're gonna multiply it by 15. That's the same as adding 561 to itself 15 times.
Step 1: 0 + 561 = 561
Step 2: 561 + 561 = 1122
Step 3: 1122 + 561 = 1683
Step 4: 1683 + 561 = 2244
Step 5: 2244 + 561 = 2805
Step 6: 2805 + 561 = 3366
Step 7: 3366 + 561 = 3927
Step 8: 3927 + 561 = 4488
Step 9: 4488 + 561 = 5049
Step 10: 5049 + 561 = 5610
Step 11: 5610 + 561 = 6171
Step 12: 6171 + 561 = 6732
Step 13: 6732 + 561 = 7293
Step 14: 7293 + 561 = 7854
Step 15: 7854 + 561 = 8415

So, 561*15 = 8415