Let's get this math done. We have 337 and we're going to multiply it by 15. This is the same as taking 337 and adding it to itself 15 times.
Step 1: 0 + 337 = 337
Step 2: 337 + 337 = 674
Step 3: 674 + 337 = 1011
Step 4: 1011 + 337 = 1348
Step 5: 1348 + 337 = 1685
Step 6: 1685 + 337 = 2022
Step 7: 2022 + 337 = 2359
Step 8: 2359 + 337 = 2696
Step 9: 2696 + 337 = 3033
Step 10: 3033 + 337 = 3370
Step 11: 3370 + 337 = 3707
Step 12: 3707 + 337 = 4044
Step 13: 4044 + 337 = 4381
Step 14: 4381 + 337 = 4718
Step 15: 4718 + 337 = 5055

So, 337*15 = 5055