直接写出下列各题的得数，你是最快的！
2.1+3.4=________720-80=________2.6-1.7=________1.4-0.6=________0.3×40=________1.25×3×8=________3.8×0=________0.9+99×0.9=________7÷1.4=________390×0.02=________2.5+1.8=________6.5×4×0.2=________8×=________÷=________44÷=________4×（0.6+1.9）=________+=________0.9-0.26=________14.5+9.5=________（0.18+0.9）÷9=________18÷36=________1.9×4×0.5=________7.2÷8×4=________78-0.8=________62-35=________20×5.5=________1.68+1.5=________×12=________8.3+1.7=________11.3-8.6=________2.4-0.5=________÷=________+=________3.25×4=________÷2=________÷3=________24×5=________0.77+0.33=________×=________12.6÷3=________3.14×25=________3.14×36=________0.082=________8л=________1.4：________==________÷10=________%
网友回答
5.5 640 0.9 0.8 12 30 0 90 5 7.8 4.3 5.2 6 1 40 10 0.64 24 0.12 0.5 3.8 3.6 77.2 27 110 3.18 9 10 2.7 1.9 2 13 120 1.1 4.2 78.5 113.04 0.0064 25.12 1.75 8 80
解析分析：依据四则运算计算方法，以及比与分数，除式，百分数互化求解．
解答：2.1+3.4=5.5；720-80=640；2.6-1.7=0.9；1.4-0.6=0.8；0.3×40=12； 1.25×3×8=30；3.8×0=0；0.9+99×0.9=90；7÷1.4=5；390×0.02=7.8；2.5+1.8=4.3；6.5×4×0.2=5.2；8×=6；÷=1；44÷=40；4×（0.6+1.9）=10；+=；0.9-0.26=0.64；14.5+9.5=24；（0.18+0.9）÷9=0.12；18÷36=0.5；1.9×4×0.5=3.8；7.2÷8×4=3.6；78-0.8=77.2；62-35=27；20×5.5=110；1.68+1.5=3.18；×12=9；8.3+1.7=10；11.3-8.6=2.7；2.4-0.5=1.9；÷=；+=2；3.25×4=13；÷2=；÷3=；24×5=120；0.77+0.33=1.1；×=；12.6÷3=4.2；3.14×25=78.5；3.14×36=113.04；0.082=0.0064；8л=25.12；1.4：1.75==8÷10=80%．故