分析:(1)根據(jù)加法交換律進(jìn)行計(jì)算;
(2)根據(jù)加法交換律進(jìn)行計(jì)算;
(3)根據(jù)加法交換律進(jìn)行計(jì)算;
(4)根據(jù)加法交換律和結(jié)合律以及連減的性質(zhì)進(jìn)行計(jì)算;
(5)按照從左向右的順序進(jìn)行計(jì)算;
(6)按照從左向右的順序進(jìn)行計(jì)算;
(7)根據(jù)連減的性質(zhì)進(jìn)行計(jì)算;
(8)根據(jù)加法交換律和結(jié)合律進(jìn)行計(jì)算.
解答:解:
(1)8.38+9.43+6.62,
=8.38+6.62+9.43,
=15+9.43,
=24.93;
(2)5.86-1.77+2.54,
=5.86+2.54-1.77,
=8.4-1.77,
=6.63;
(3)47.2+8.6-7.2,
=47.2-7.2+8.6,
=40+8.6,
=48.6;
(4)28.6-3.8-14.6-6.2,
=(28.6-14.6)-(3.8+6.2),
=14-10,
=4;
(5)8-2.6-1.77,
=5.4-1.77,
=3.63;
(6)7.4+0.93-4.36,
=8.33-4.36,
=3.97;
(7)17.34-(9.8+6.34),
=17.34-9.8-6.34,
=17.34-6.34-9.8,
=11-9.8,
=1.2;
(8)0.93+5.45+7.07+4.55,
=(0.93+7.07)+(5.45+4.55),
=8+10,
=18.
點(diǎn)評:考查了運(yùn)算定律與簡便運(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)算律簡便計(jì)算.