Let's get this math done. We have 352 and we're going to multiply it by 15. This is the same as taking 352 and adding it to itself 15 times.
Step 1: 0 + 352 = 352
Step 2: 352 + 352 = 704
Step 3: 704 + 352 = 1056
Step 4: 1056 + 352 = 1408
Step 5: 1408 + 352 = 1760
Step 6: 1760 + 352 = 2112
Step 7: 2112 + 352 = 2464
Step 8: 2464 + 352 = 2816
Step 9: 2816 + 352 = 3168
Step 10: 3168 + 352 = 3520
Step 11: 3520 + 352 = 3872
Step 12: 3872 + 352 = 4224
Step 13: 4224 + 352 = 4576
Step 14: 4576 + 352 = 4928
Step 15: 4928 + 352 = 5280

So, 352*15 = 5280