OK, let's crack this. We're given 80 and our task is to multiply it by 68. Essentially, we'll be adding 80 to itself 68 times.
Step 1: 0 + 80 = 80
Step 2: 80 + 80 = 160
Step 3: 160 + 80 = 240
Step 4: 240 + 80 = 320
Step 5: 320 + 80 = 400
Step 6: 400 + 80 = 480
Step 7: 480 + 80 = 560
Step 8: 560 + 80 = 640
Step 9: 640 + 80 = 720
Step 10: 720 + 80 = 800
Step 11: 800 + 80 = 880
Step 12: 880 + 80 = 960
Step 13: 960 + 80 = 1040
Step 14: 1040 + 80 = 1120
Step 15: 1120 + 80 = 1200
Step 16: 1200 + 80 = 1280
Step 17: 1280 + 80 = 1360
Step 18: 1360 + 80 = 1440
Step 19: 1440 + 80 = 1520
Step 20: 1520 + 80 = 1600
Step 21: 1600 + 80 = 1680
Step 22: 1680 + 80 = 1760
Step 23: 1760 + 80 = 1840
Step 24: 1840 + 80 = 1920
Step 25: 1920 + 80 = 2000
Step 26: 2000 + 80 = 2080
Step 27: 2080 + 80 = 2160
Step 28: 2160 + 80 = 2240
Step 29: 2240 + 80 = 2320
Step 30: 2320 + 80 = 2400
Step 31: 2400 + 80 = 2480
Step 32: 2480 + 80 = 2560
Step 33: 2560 + 80 = 2640
Step 34: 2640 + 80 = 2720
Step 35: 2720 + 80 = 2800
Step 36: 2800 + 80 = 2880
Step 37: 2880 + 80 = 2960
Step 38: 2960 + 80 = 3040
Step 39: 3040 + 80 = 3120
Step 40: 3120 + 80 = 3200
Step 41: 3200 + 80 = 3280
Step 42: 3280 + 80 = 3360
Step 43: 3360 + 80 = 3440
Step 44: 3440 + 80 = 3520
Step 45: 3520 + 80 = 3600
Step 46: 3600 + 80 = 3680
Step 47: 3680 + 80 = 3760
Step 48: 3760 + 80 = 3840
Step 49: 3840 + 80 = 3920
Step 50: 3920 + 80 = 4000
Step 51: 4000 + 80 = 4080
Step 52: 4080 + 80 = 4160
Step 53: 4160 + 80 = 4240
Step 54: 4240 + 80 = 4320
Step 55: 4320 + 80 = 4400
Step 56: 4400 + 80 = 4480
Step 57: 4480 + 80 = 4560
Step 58: 4560 + 80 = 4640
Step 59: 4640 + 80 = 4720
Step 60: 4720 + 80 = 4800
Step 61: 4800 + 80 = 4880
Step 62: 4880 + 80 = 4960
Step 63: 4960 + 80 = 5040
Step 64: 5040 + 80 = 5120
Step 65: 5120 + 80 = 5200
Step 66: 5200 + 80 = 5280
Step 67: 5280 + 80 = 5360
Step 68: 5360 + 80 = 5440

So, 80*68 = 5440