考點:整數(shù)四則混合運算,運算定律與簡便運算,小數(shù)四則混合運算
專題:運算順序及法則
分析:(1)(4)(8)(9)運用加法交換律與結(jié)合律簡算.
(2)運用乘法分配律簡算.
(3)把101看作100+1,運用乘法分配律簡算.
(5)(6)(7)運用減法的性質(zhì)簡算.
解答:
解:(1)98+265+202
=(98+202)+265
=300+265
=565
(2)105×26-5×26
=(105-5)×26
=100×26
=2600
(3)101×87
=(100+1)×87
=100×87+87
=8700+87
=8787
(4)5.6+2.7+4.4
=(5.6+4.4)+2.7
=10+2.7
=12.7
(5)9.14-1.43-4.57
=9.14-(1.43+4.57)
=9.14-6
=3.14
(6)9.84-(2.84+1.86)
=(9.84-2.84)-1.86
=7-1.86
=5.14
(7)5.17-1.8-3.2
=5.17-(1.8+3.2)
=5.17-5
=0.17
(8)4.02-3.5+0.98
=(4.02+0.98)-3.5
=5-3.5
=1.5
(9)13.7+0.98+0.02+4.3
=(13.7+4.3)+(0.98+0.02)
=18+1
=19
點評:此題主要考查整數(shù)的四則混合運算的運算順序和應(yīng)用運算定律進行簡便計算.