16.簡便方法計(jì)算,寫出主要計(jì)算過程.
6.12+37+2.88+47; 1811-(711+38); 825+713+1725+613.
分析 (1)根據(jù)加法交換律和結(jié)合律簡算;
(2)根據(jù)減法的性質(zhì)簡算;
(3)根據(jù)加法交換律和結(jié)合律簡算.
解答 解:(1)6.12+37+2.88+47
=(6.12+2.88)+(37+47)
=9+1
=10
(2)1811-(711+38)
=1811-711-38
=1-38
=58
(3)825+713+1725+613
=(825+1725)+(713+613)
=1+1
=2
點(diǎn)評 此題是考查四則混合運(yùn)算,要仔細(xì)觀察算式的特點(diǎn),靈活運(yùn)用一些定律進(jìn)行簡便計(jì)算.