One can resort to traditional vertical multiplication (which requires patience), or do
897*394 = (900-3) * (400-6) = 900*400 - 6*900 - 400*3 + 3*6 = 360,000 - (5,400 + 1,200) + 18 = 360,018 - 6,600 = 353,418
897*394 = (900-3) * (400-6) = 900*400 - 6*900 - 400*3 + 3*6 = 360,000 - (5,400 + 1,200) + 18 = 360,018 - 6,600 = 353,418
8*3=24 and 800*300 =240000
8*9=72 and 800* 90 = 72000
8*4=32 and 800* 4 = 3200
9*3=27 and 90*300 = 27000
9*9=81 and 90* 90 = 8100
9*4=36 and 90* 4 = 360
7*3=21 and 7*300 = 2100
7*9=63 and 7* 90 = 630
7*4=28 and 7* 4 = 28
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