Sure thing, let's get straight to it. We start with 537 and we're going to multiply it by 40, which means adding 537 to itself 40 times.
Step 1: 0 + 537 = 537
Step 2: 537 + 537 = 1074
Step 3: 1074 + 537 = 1611
Step 4: 1611 + 537 = 2148
Step 5: 2148 + 537 = 2685
Step 6: 2685 + 537 = 3222
Step 7: 3222 + 537 = 3759
Step 8: 3759 + 537 = 4296
Step 9: 4296 + 537 = 4833
Step 10: 4833 + 537 = 5370
Step 11: 5370 + 537 = 5907
Step 12: 5907 + 537 = 6444
Step 13: 6444 + 537 = 6981
Step 14: 6981 + 537 = 7518
Step 15: 7518 + 537 = 8055
Step 16: 8055 + 537 = 8592
Step 17: 8592 + 537 = 9129
Step 18: 9129 + 537 = 9666
Step 19: 9666 + 537 = 10203
Step 20: 10203 + 537 = 10740
Step 21: 10740 + 537 = 11277
Step 22: 11277 + 537 = 11814
Step 23: 11814 + 537 = 12351
Step 24: 12351 + 537 = 12888
Step 25: 12888 + 537 = 13425
Step 26: 13425 + 537 = 13962
Step 27: 13962 + 537 = 14499
Step 28: 14499 + 537 = 15036
Step 29: 15036 + 537 = 15573
Step 30: 15573 + 537 = 16110
Step 31: 16110 + 537 = 16647
Step 32: 16647 + 537 = 17184
Step 33: 17184 + 537 = 17721
Step 34: 17721 + 537 = 18258
Step 35: 18258 + 537 = 18795
Step 36: 18795 + 537 = 19332
Step 37: 19332 + 537 = 19869
Step 38: 19869 + 537 = 20406
Step 39: 20406 + 537 = 20943
Step 40: 20943 + 537 = 21480

So, 537*40 = 21480