下面各题怎样简便怎样算.6.13+28.86+13.87+1.1412×97+1.2×3071÷60-68×1608.8×(3.75-1.25)×1.25(34+815×512)÷3536(49-241)×9×41.-数学
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答案
(1)6.13+28.86+13.87+1.14, =(6.13+13.87)+(28.86+1.14), =20+30, =50; (2)12×97+1.2×30, =12×(97+3), =12×100, =1200; (3)71÷60-68×
=(71-68)×
=3×
=0.05; (4)8.8×(3.75-1.25)×1.25, =[(8+0.8)×1.25]×2.5, =[8×1.25+0.8×1.25]×2.5, =[10+1]×2.5, =10×2.5+1×2.5, =25+2.5, =27.5; (5)(
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