分析:橫向數(shù):(1)(2)依據(jù)整數(shù)四則運(yùn)算計(jì)算方法解答;
(3)化2.4=4×0.6,再運(yùn)用乘法結(jié)合律解答;
(4)(5)(6)(8)(9)(10)(11)(12)(15)(16)依據(jù)分?jǐn)?shù)四則運(yùn)算計(jì)算方法解答;
(7)運(yùn)用乘法交換律和結(jié)合律解答;
(13)運(yùn)用乘法分配律解答;
(14)把12.01看作12,9.98看作10解答.
解答:
解:180+470=650; |
5÷8=0.625; |
25×2.4=60; |
12-=11; |
÷14=; |
+=; |
1.25××0.8=; |
×=0.4; |
÷=2; |
-=; |
×4÷4×=; |
2.4×=0.9; |
(+)×16=6; |
12.01×9.98≈120; |
2÷0.2%=1000; |
60×20%=12. |
點(diǎn)評(píng):本題主要考查學(xué)生依據(jù)四則運(yùn)算計(jì)算方法解決問(wèn)題的能力,解答時(shí)注意:有簡(jiǎn)便算法的要正確的選擇并應(yīng)用運(yùn)算定律進(jìn)行簡(jiǎn)便計(jì)算.