Sure thing, let's get straight to it. We start with 523 and we're going to multiply it by 15, which means adding 523 to itself 15 times.
Step 1: 0 + 523 = 523
Step 2: 523 + 523 = 1046
Step 3: 1046 + 523 = 1569
Step 4: 1569 + 523 = 2092
Step 5: 2092 + 523 = 2615
Step 6: 2615 + 523 = 3138
Step 7: 3138 + 523 = 3661
Step 8: 3661 + 523 = 4184
Step 9: 4184 + 523 = 4707
Step 10: 4707 + 523 = 5230
Step 11: 5230 + 523 = 5753
Step 12: 5753 + 523 = 6276
Step 13: 6276 + 523 = 6799
Step 14: 6799 + 523 = 7322
Step 15: 7322 + 523 = 7845

So, 523*15 = 7845