分析:(1)(5)可根據(jù)加法交換律進(jìn)行計(jì)算;
(2)(6)可根據(jù)一個(gè)數(shù)減兩個(gè)數(shù),等于用這個(gè)數(shù)減去這兩個(gè)數(shù)的和的減法性質(zhì)計(jì)算;
(3)可根據(jù)一個(gè)數(shù)減兩個(gè)數(shù)的和,等于用這個(gè)數(shù)分別、減去這兩個(gè)數(shù)的減法性質(zhì)計(jì)算;
(4)按從左到右的順序計(jì)算即可;
(5)可根據(jù)加法交換律計(jì)算.
解答:解:(1)4.32+5.43+6.68
=4.32+6.68+5.43,
=11+5.43,
=16.43;
(2)15.17-6.8-3.2
=15.17-(6.8+3.2),
=15.17-10,
=5.17;
(3)34.82-(4.82+15.2)
=34.82-4.82-15.2,
=30-15.2,
=14.8;
(4)15.27+4.72-5.28
=19.99-5.28,
=14.71;
(5)4.02-3.5+0.98
=4.02+0.98-3.5,
=5-3.5,
=1.5;
(6)5.8-4.5+5.8-4.5
=5.8+5.8-(4.5+4.5),
=11.6-9,
=2.6.
點(diǎn)評(píng):完成本題要注意分析式中數(shù)據(jù)的特點(diǎn),然后運(yùn)用合適的方法進(jìn)行計(jì)算.