Alright, let's solve this math problem step by step. First, we have the number 687. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 66. So, we're going to take the number 687 and add it to itself 66 times.
Step 1: 0 + 687 = 687
Step 2: 687 + 687 = 1374
Step 3: 1374 + 687 = 2061
Step 4: 2061 + 687 = 2748
Step 5: 2748 + 687 = 3435
Step 6: 3435 + 687 = 4122
Step 7: 4122 + 687 = 4809
Step 8: 4809 + 687 = 5496
Step 9: 5496 + 687 = 6183
Step 10: 6183 + 687 = 6870
Step 11: 6870 + 687 = 7557
Step 12: 7557 + 687 = 8244
Step 13: 8244 + 687 = 8931
Step 14: 8931 + 687 = 9618
Step 15: 9618 + 687 = 10305
Step 16: 10305 + 687 = 10992
Step 17: 10992 + 687 = 11679
Step 18: 11679 + 687 = 12366
Step 19: 12366 + 687 = 13053
Step 20: 13053 + 687 = 13740
Step 21: 13740 + 687 = 14427
Step 22: 14427 + 687 = 15114
Step 23: 15114 + 687 = 15801
Step 24: 15801 + 687 = 16488
Step 25: 16488 + 687 = 17175
Step 26: 17175 + 687 = 17862
Step 27: 17862 + 687 = 18549
Step 28: 18549 + 687 = 19236
Step 29: 19236 + 687 = 19923
Step 30: 19923 + 687 = 20610
Step 31: 20610 + 687 = 21297
Step 32: 21297 + 687 = 21984
Step 33: 21984 + 687 = 22671
Step 34: 22671 + 687 = 23358
Step 35: 23358 + 687 = 24045
Step 36: 24045 + 687 = 24732
Step 37: 24732 + 687 = 25419
Step 38: 25419 + 687 = 26106
Step 39: 26106 + 687 = 26793
Step 40: 26793 + 687 = 27480
Step 41: 27480 + 687 = 28167
Step 42: 28167 + 687 = 28854
Step 43: 28854 + 687 = 29541
Step 44: 29541 + 687 = 30228
Step 45: 30228 + 687 = 30915
Step 46: 30915 + 687 = 31602
Step 47: 31602 + 687 = 32289
Step 48: 32289 + 687 = 32976
Step 49: 32976 + 687 = 33663
Step 50: 33663 + 687 = 34350
Step 51: 34350 + 687 = 35037
Step 52: 35037 + 687 = 35724
Step 53: 35724 + 687 = 36411
Step 54: 36411 + 687 = 37098
Step 55: 37098 + 687 = 37785
Step 56: 37785 + 687 = 38472
Step 57: 38472 + 687 = 39159
Step 58: 39159 + 687 = 39846
Step 59: 39846 + 687 = 40533
Step 60: 40533 + 687 = 41220
Step 61: 41220 + 687 = 41907
Step 62: 41907 + 687 = 42594
Step 63: 42594 + 687 = 43281
Step 64: 43281 + 687 = 43968
Step 65: 43968 + 687 = 44655
Step 66: 44655 + 687 = 45342

So, 687*66 = 45342