Without delay, let's solve this. We've got 80 and we will be multiplying it by 40, that is, adding 80 to itself 40 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

So, 80*40 = 3200