Let's get this math done. We have 540 and we're going to multiply it by 23. This is the same as taking 540 and adding it to itself 23 times.
Step 1: 0 + 540 = 540
Step 2: 540 + 540 = 1080
Step 3: 1080 + 540 = 1620
Step 4: 1620 + 540 = 2160
Step 5: 2160 + 540 = 2700
Step 6: 2700 + 540 = 3240
Step 7: 3240 + 540 = 3780
Step 8: 3780 + 540 = 4320
Step 9: 4320 + 540 = 4860
Step 10: 4860 + 540 = 5400
Step 11: 5400 + 540 = 5940
Step 12: 5940 + 540 = 6480
Step 13: 6480 + 540 = 7020
Step 14: 7020 + 540 = 7560
Step 15: 7560 + 540 = 8100
Step 16: 8100 + 540 = 8640
Step 17: 8640 + 540 = 9180
Step 18: 9180 + 540 = 9720
Step 19: 9720 + 540 = 10260
Step 20: 10260 + 540 = 10800
Step 21: 10800 + 540 = 11340
Step 22: 11340 + 540 = 11880
Step 23: 11880 + 540 = 12420

So, 540*23 = 12420