分析:(1)(2)(5)(10)(11)(17)(18)(22)屬于小數(shù)乘法,去掉小數(shù)點(diǎn),整數(shù)相乘,然后在結(jié)果中從后向前數(shù)出小數(shù)的位數(shù),點(diǎn)上小數(shù)點(diǎn);(3)(7)(8)(12)(13)(14)(20)屬于小數(shù)除法,根據(jù)自身特點(diǎn),把被除數(shù)和除數(shù)分別擴(kuò)大相同的倍數(shù),再計(jì)算;(4)此題除不盡,而且得數(shù)是循環(huán)小數(shù),結(jié)果用循環(huán)節(jié)表示;(6)(9)(15)(16)屬于小數(shù)的加減運(yùn)算,注意小數(shù)點(diǎn)對齊;(19)1乘任何數(shù)都得原數(shù);(21)把102看作100+2,運(yùn)用乘法分配律簡算;(23)運(yùn)用乘法交換律與結(jié)合律簡算;(24)運(yùn)用減法的性質(zhì)簡算;(25)運(yùn)用乘法分配律簡算.
解答:解:9.1×3=27.3; 0.8×7=5.6; 5.6÷2=2.8; 11÷3=3.
; 40×0.5=20;
10-0.1=9.9; 2.48÷0.8=3.1; 2.1÷0.7=3; 5.2+0.08=5.28; 0.3×1.7=0.51;
0.5×1.8=0.9; 0.84÷7=0.12; 0.54÷0.6=0.9; 3.9÷39=0.1; 2.4-1.8=0.6;
0.32+1.28=1.6; 3×0.09=0.27; 0.9×0.9=0.81; 1×8.02=8.02; 6.5÷1.3=5;
1.5×102=153; 4×0.25=1; 1.25×1.4×8=14; 15-1.7-1.3=12; 4.3×99+4.3=430.
點(diǎn)評:此題考查的知識面較廣,根據(jù)題目特點(diǎn),靈活解答.