考點:運算定律與簡便運算
專題:運算定律及簡算
分析:(1)把103看作100+3,再進行計算;
(2)把201看作200+1,再進行計算;
(3)把99看作100-1,再進行計算;
(4)把396看作400-4,再進行計算;
(5)運用減法的性質(zhì)進行簡算;
(6)運用加法的交換律進行簡算;
(7)先去括號,再運用加法的結(jié)合律進行簡算;
(8)把201看作200+1,再進行計算.
解答:
解:(1)228+103
=228+100+3
=328+3
=331;
(2)233-201
=233-(200+1)
=233-200-1
=33-1
=32;
(3)456-99
=456-(100-1)
=456-100+1
=356-1
=355;
(4)396+87
=400-4+87
=400+87-4
=487-4
=483;
(5)283-114-86
=283-(114+86)
=283-200
=83;
(6)256+92+44
=256+44+92
=300+92
=392;
(7)(153+315)+85
=153+315+85
=153+(315+85)
=153+400
=553;
(8)306-197
=306-(200-3)
=306-200+3
=106+3
=109.
點評:此題主要根據(jù)加法的運算定律和減法的運算性質(zhì)進行簡算.