考點:小數(shù)四則混合運算,運算定律與簡便運算
專題:運算順序及法則,運算定律及簡算
分析:(1)(4)運用加法交換律與結合律簡算;
(2)運用減法的性質(zhì)簡算;
(3)從左往右依次運算;
(5)(6)運用加法交換律與結合律以及減法的性質(zhì)簡算;
(7)先算括號內(nèi)的,再算括號外的;
(8)把0.99看作1-0.01,運用減法的性質(zhì)簡算.
解答:
解:(1)36.87+19.38-0.87
=(36.87-0.87)+19.38
=36+19.38
=55.38
(2)68.15-6.47-4.53
=68.15-(6.47+4.53)
=68.15-11
=57.15
(3)6.36+4.43+0.749
=10.79+0.749
=11.539
(4)86.39-62.78+103.61-2.22
=(86.39+103.61)-(62.78+2.22)
=190-65
=125
(5)100.46-26.28-23.72-10.46
=(100.46-10.46)-(26.28+23.72)
=90-50
=40
(6)7.13-(5.13-0.6)
=(7.13-5.13)+0.6
=2+0.6
=2.6
(7)0.26+(52.04-46.89)
=0.26+5.15
=5.41
(8)13.86-0.99
=13.86-(1-0.01)
=13.86-1+0.01
=12.86+0.01
=12.87
點評:完成本題要注意分析式中數(shù)據(jù),運用合適的簡便方法計算.