Let's roll up our sleeves and solve this. We have 29 and we're going to multiply it by 15, essentially adding 29 to itself 15 times.
Step 1: 0 + 29 = 29
Step 2: 29 + 29 = 58
Step 3: 58 + 29 = 87
Step 4: 87 + 29 = 116
Step 5: 116 + 29 = 145
Step 6: 145 + 29 = 174
Step 7: 174 + 29 = 203
Step 8: 203 + 29 = 232
Step 9: 232 + 29 = 261
Step 10: 261 + 29 = 290
Step 11: 290 + 29 = 319
Step 12: 319 + 29 = 348
Step 13: 348 + 29 = 377
Step 14: 377 + 29 = 406
Step 15: 406 + 29 = 435

So, 29*15 = 435