OK, let's crack this. We're given 938 and our task is to multiply it by 15. Essentially, we'll be adding 938 to itself 15 times.
Step 1: 0 + 938 = 938
Step 2: 938 + 938 = 1876
Step 3: 1876 + 938 = 2814
Step 4: 2814 + 938 = 3752
Step 5: 3752 + 938 = 4690
Step 6: 4690 + 938 = 5628
Step 7: 5628 + 938 = 6566
Step 8: 6566 + 938 = 7504
Step 9: 7504 + 938 = 8442
Step 10: 8442 + 938 = 9380
Step 11: 9380 + 938 = 10318
Step 12: 10318 + 938 = 11256
Step 13: 11256 + 938 = 12194
Step 14: 12194 + 938 = 13132
Step 15: 13132 + 938 = 14070

So, 938*15 = 14070