分析:(1)(9)(10)先算17×5,25×4,125×8然后在結(jié)果中從后向前數(shù)出兩位,點(diǎn)上小數(shù)點(diǎn);(2)(3)把被除數(shù)和除數(shù)分別擴(kuò)大10倍,再計(jì)算;(4)先算40×5,然后在結(jié)果中從后向前數(shù)出一位,點(diǎn)上小數(shù)點(diǎn);(5)注意數(shù)位對(duì)齊;(6)把被除數(shù)和除數(shù)分別擴(kuò)大100倍,再計(jì)算;(7)(11)(12)注意數(shù)位對(duì)齊;(8)把0.9的小數(shù)點(diǎn)向左移動(dòng)兩位即可.
解答:解:0.17×5=0.85; 8.4÷0.7=12; 14.4÷1.2=12; 40×0.5=20; 0.65÷13=0.05; 0.96÷0.06=16;
0.45+0.55=1; 0.9×0.01=0.009; 2.5×0.4=1; 1.25×8=10; 18+1.2=19.2; 0.56+14=14.56;
故答案為:0.85,12,12,20,0.05,16,1,0.009,1,10,19.2,14.56.
點(diǎn)評(píng):此題考查了小數(shù)的加、減、乘、除運(yùn)算,根據(jù)題目特點(diǎn),靈活解答.