人教版小学数学五年级下册第五单元分数加减混合运算第一课时

技术官员村位于位于亚运城东部，主干道二以东石楼涌以西的地块，占地面积、m2，总建筑面积、m2，共包括地下室南区、地下室北区、地上部分1栋～12栋、服务中心、室外工程等多个单体工程。其中住宅面积m2，共12栋，1～7栋建筑层数为11层，8～12栋11层（局部复式顶层），首层局部架空，布置公建配套设施。integratedenergy,chemicalsandtextileYibincity,arethethreecorepillarsoftheindustry.In2014,thewuliangyebrandvalueto73.58billionyuan,thecity'sliquorindustrysliptostabilise.Promotingdeepdevelopmentofintegratedenergy,advancedequipmentmanufacturingindustry,changningdistrict,shalegasproductioncapacityreached277millioncubicmetres,builtthecountry'sfirstindependenthigh-yieldwellsandpipelinesinthefirstsection,theleadinfactoryproductionandsupplytothepopulation.2.1-3GDPgrowthfigure2.1-4Yibin,Yibincity,Yibincity,fiscalrevenuegrowth2.1.4topographyterrainoverallisSouthwest,North-EasternState.Lowmountainsandhillsinthecitylandscapeasthemainridge-and-Valley,pingbasmallfragmentednaturepictureforwaterandthesecondlandofthesevenhills.236metersto2000metersabovesealevelinthecity,lowmountain,46.6%hills45.3%,pingbaonly8.1%.2.1.5developmentofYibinlandscapesanddistinctivefeatureinthecenterofthecity,withlimitations,andspatialstructureoftypicalzonalgroup,2012-citiesinbuildingwithanareaofabout76.2km2.Fromcity-buildingsituation,oldtown-theSouthBankCenterconstructionislaggingbehind,disintegrationoftheoldcityisslow,optimizationandupgrading,qualitypublicserviceresourcesarestillheavilyconcentratedintheoldtowntogether.SouthbankCentrehasnotbeenformed,functionsoftheserviceareaspaceismissing.Meanwhile,peripheralgroupcentresservicewasweakandinadequateaccountingforcitydevelopment,suspiciouspatterncouldnotbeformed.Asregardstransport,withtheoutwardexpansionofcities,citieshavebeenexpanding,centripetalcitytrafficorganizationhasnotchanged,integratedenergy,chemicalsandtextileYibincity,arethethreecorepillarsoftheindustry.In2014,thewuliangyebrandvalueto73.58billionyuan,thecity'sliquorindustrysliptostabilise.Promotingdeepdevelopmentofintegratedenergy,advancedequipmentmanufacturingindustry,changningdistrict,shalegasproductioncapacityreached277millioncubicmetres,builtthecountry'sfirstindependenthigh-yieldwellsandpipelinesinthefirstsection,theleadinfactoryproductionandsupplytothepopulation.2.1-3GDPgrowthfigure2.1-4Yibin,Yibincity,Yibincity,fiscalrevenuegrowth2.1.4topographyterrainoverallisSouthwest,North-EasternState.Lowmountainsandhillsinthecitylandscapeasthemainridge-and-Valley,pingbasmallfragmentednaturepictureforwaterandthesecondlandofthesevenhills.236metersto2000metersabovesealevelinthecity,lowmountain,46.6%hills45.3%,pingbaonly8.1%.2.1.5developmentofYibinlandscapesanddistinctivefeatureinthecenterofthecity,withlimitations,andspatialstructureoftypicalzonalgroup,2012-citiesinbuildingwithanareaofabout76.2km2.Fromcity-buildingsituation,oldtown-theSouthBankCenterconstructionislaggingbehind,disintegrationoftheoldcityisslow,optimizationandupgrading,qualitypublicserviceresourcesarestillheavilyconcentratedintheoldtowntogether.SouthbankCentrehasnotbeenformed,functionsoftheserviceareaspaceismissing.Meanwhile,peripheralgroupcentresservicewasweakandinadequateaccountingforcitydevelopment,suspiciouspatterncouldnotbeformed.Asregardstransport,withtheoutwardexpansionofcities,citieshavebeenexpanding,centripetalcitytrafficorganizationhasnotchanged,课题：分数加减混合运算(一)教学目标1、通过教学，使学生掌握分数加减混合运算的顺序和计算方法，并掌握带有小括号的分数加减混合运算的顺序及算法。2、培养学生迁移、类推的能力和归纳、概括的能力。3、养成用简明、灵活的方法解决问题的习惯。重点难点掌握分数加减混合运算的顺序和计算方法。教学过程第一课时一、复习导入1．说一说下列各题的运算顺序。112+8-1316-4+2124-(18+3)2.老师指出：分数加减混合运算的运算顺序和整数加减混合运算的运算顺序相同。[设计意图]这一环节，通过形象生动的课件，激发学生的学习兴趣，不仅温习了旧知，而且也为学生学习新知架起了桥梁。真正起到了承上启下的作用二、探究新知1．出示例1的表格。地貌类型占公园面积的几分之几乔木林21灌木丛103草地51(1)从表格中你能得到哪些数学信息？表中各分数表示什么意思？(2）你能提出那些数学问题？生：乔木林比灌木丛多几分之几？乔木林比草地多几分之几？乔木林、灌木丛和草地共占公园面积的几分之几？(3）老师出示一个问题：“森林部分比草地部分多几分之几？(4）提问：森林部分指什么？怎样列式？(5）请学生试着算一算，集体交流计算方法。技术官员村位于位于亚运城东部，主干道二以东石楼涌以西的地块，占地面积、m2，总建筑面积、m2，共包括地下室南区、地下室北区、地上部分1栋～12栋、服务中心、室外工程等多个单体工程。其中住宅面积m2，共12栋，1～7栋建筑层数为11层，8～12栋11层（局部复式顶层），首层局部架空，布置公建配套设施。integratedenergy,chemicalsandtextileYibincity,arethethreecorepillarsoftheindustry.In2014,thewuliangyebrandvalueto73.58billionyuan,thecity'sliquorindustrysliptostabilise.Promotingdeepdevelopmentofintegratedenergy,advancedequipmentmanufacturingindustry,changningdistrict,shalegasproductioncapacityreached277millioncubicmetres,builtthecountry'sfirstindependenthigh-yieldwellsandpipelinesinthefirstsection,theleadinfactoryproductionandsupplytothepopulation.2.1-3GDPgrowthfigure2.1-4Yibin,Yibincity,Yibincity,fiscalrevenuegrowth2.1.4topographyterrainoverallisSouthwest,North-EasternState.Lowmountainsandhillsinthecitylandscapeasthemainridge-and-Valley,pingbasmallfragmentednaturepictureforwaterandthesecondlandofthesevenhills.236metersto2000metersabovesealevelinthecity,lowmountain,46.6%hills45.3%,pingbaonly8.1%.2.1.5developmentofYibinlandscapesanddistinctivefeatureinthecenterofthecity,withlimitations,andspatialstructureoftypicalzonalgroup,2012-citiesinbuildingwithanareaofabout76.2km2.Fromcity-buildingsituation,oldtown-theSouthBankCenterconstructionislaggingbehind,disintegrationoftheoldcityisslow,optimizationandupgrading,qualitypublicserviceresourcesarestillheav