考點(diǎn):小數(shù)的加法和減法,整數(shù)四則混合運(yùn)算
專題:運(yùn)算順序及法則
分析:(1)把4.95化成5-0.05,再計(jì)算即可;
(2)先算小括號(hào)里的減法,再算中括號(hào)里的加法,最后算括號(hào)外的減法;
(3)先算除法,再算乘法,最后算減法;
(4)從左向右進(jìn)行計(jì)算即可;
(5)把9.74化成10-0.26,再計(jì)算即可;
(6)先算小括號(hào)里的減法,再算中括號(hào)里的乘法,最后算括號(hào)外的除法.
解答:
解(1)8.3+4.95
=8.3+5-0.05
=13.3-0.05
=13.25;
(2)40-[1.25+(3.5-2.75)]
=40-[1.25+0.75]
=40-2
=38;
(3)1356-185÷5×34
=1356-37×34
=1356-1258
=98;
(4)11.68+7.9-11.95
=19.58-11.95
=7.63;
(5)21.6-9.74
=21.6-10+0.26
=11.6+0.26
=11.86;
(6)2592÷[(71-59)×6]
=2592÷[12×6]
=2592÷72
=36.
點(diǎn)評(píng):此題考查了整數(shù)、小數(shù)四則混合運(yùn)算的順序,注意有括號(hào)的要先算括號(hào)里的運(yùn)算.