Let's get this math done. We have 153 and we're going to multiply it by 9. This is the same as taking 153 and adding it to itself 9 times.
Step 1: 0 + 153 = 153
Step 2: 153 + 153 = 306
Step 3: 306 + 153 = 459
Step 4: 459 + 153 = 612
Step 5: 612 + 153 = 765
Step 6: 765 + 153 = 918
Step 7: 918 + 153 = 1071
Step 8: 1071 + 153 = 1224
Step 9: 1224 + 153 = 1377

So, 153*9 = 1377