考點:運算定律與簡便運算
專題:運算定律及簡算
分析:①227+365+473,運用加法交換律和結(jié)合律簡算;
②752-398,根據(jù)減法的運算性質(zhì)簡算;
③952-69-131,根據(jù)減法的運算性質(zhì)簡算;
④366+252+34+548,運用加法交換律和結(jié)合律簡算;
⑤457+97,根據(jù)加法的運算性質(zhì)簡算;
⑥235-90+165,根據(jù)加、減法的運算性質(zhì)簡算.
解答:
解:①227+365+473
=365+(227+473)
=365+700
=1065;
②752-398
=752-400+2
=354;
③952-69-131
=952-(69+131)
=952-200
=752;
④366+252+34+548
=(366+34)+(252+548)
=400+800
=1200;
⑤457+97
=457+100-3
=554;
⑥235-90+165
=235+165-90
=400-90
=310.
點評:此題考查的目的是理解掌握加法、減法的運算性質(zhì)和加法的運算定律,并且能夠靈活運用這些運算性質(zhì)和運算定律進行簡便計算.