递等式计算(能简便的要简便)①25.3×12-33.46÷0.35②12.74-0.125+2.26-9.875③(38+56)÷124④2.5×13×0.4⑤89÷[(25+110)×34]⑥45+45×19.-数学
题文
递等式计算(能简便的要简便) ①25.3×12-33.46÷0.35 ②12.74-0.125+2.26-9.875 ③(
④2.5×13×0.4 ⑤
⑥
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答案
①25.3×12-33.46÷0.35 =303.6-95.6 =208; ②12.74-0.125+2.26-9.875 =(12.74+2.26)-(0.125+9.875) =15-10 =10; ③(
=(
=
=9+20 =29; ④2.5×13×0.4 =2.5×0.4×13 =1×13 =13; ⑤
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