計(jì)算下面各題,能簡(jiǎn)算的要簡(jiǎn)算.
(1)(6.8-5.4)×2.75-0.9
(2)3.8×5.6+4.4×3.8
(3)1.24×8.3+8.3×1.76
(4)88×0.25×9.
解:
(1)(6.8-5.4)×2.75-0.9,
=1.4×2.75-0.9,
=3.85-0.9,
=2.95;
(2)3.8×5.6+4.4×3.8,
=3.8×(5.6+4.4),
=3.8×10,
=38;
(3)1.24×8.3+8.3×1.76,
=(1.24+1.76)×8.3,
=3×8.3,
=24.9;
(4)88×0.25×9,
=22×9,
=198.
分析:(1)先算小括號(hào)里面的減法.再算乘法,最后算括號(hào)外面的減法;
(2)根據(jù)乘法分配律進(jìn)行計(jì)算;
(3)根據(jù)乘法分配律進(jìn)行計(jì)算;
(4)按照從左向右的順序進(jìn)行計(jì)算.
點(diǎn)評(píng):考查了運(yùn)算定律與簡(jiǎn)便運(yùn)算,四則混合運(yùn)算.注意運(yùn)算順序和運(yùn)算法則,靈活運(yùn)用所學(xué)的運(yùn)算律簡(jiǎn)便計(jì)算.