解:(1)4.3+0.98+0.7,
=(4.3+0.7)+0.98,
=5+0.98,
=5.98;
(2)5.27-3.9-0.1,
=5.27-(3.9+0.1),
=5.27-4,
=1.27;
(3)8.44-(5.44+2.8),
=8.44-5.44-2.8,
=3-2.8,
=0.2;
(4)4.9+0.1-4.9+0.1,
=4.9-4.9+0.1+0.1,
=0+0.1+0.1,
=0+0.1+0.1,
=0.2.
分析:(1)4.3+0.98+0.7,運(yùn)用加法交換律和結(jié)合律進(jìn)行簡(jiǎn)算;
(2)5.27-3.9-0.1,根據(jù)減法的運(yùn)算性質(zhì)進(jìn)行簡(jiǎn)算;
(3)8.44-(5.44+2.8),根據(jù)減法的運(yùn)算性質(zhì)進(jìn)行簡(jiǎn)算;
(4)4.9+0.1-4.9+0.1,根據(jù)加、減法的運(yùn)算性質(zhì)進(jìn)行簡(jiǎn)算.
點(diǎn)評(píng):此題考查的目的是理解加、減法的運(yùn)算性質(zhì)、加法交換律、加法交換律的意義,并且能夠運(yùn)用這些運(yùn)算性質(zhì)、運(yùn)算定律進(jìn)行簡(jiǎn)便計(jì)算.