ideological and theoretical qualities and practical working ability, and strive to build a contingent of league cadres with positive work style and high quality. Hold a regular meting of the party secretary every fortnightly, arrange the work of the regiment, fedback the student information. Focus on training junior high school, junior high school secretary of the regiment branch to enable them to raise A firm political conviction, diligent and diligent learning spirit and practical and innovative work style.正数和负数班级: 姓名: 【学习目标】1.通过生活实例感受生活中的正数和负数;2.会用正数、负数表示意义相反的量;3.了解整数和分数分类.【重、难点】重点:1.理解正数与负数的意义.2.用正数、负数表示意义相反的量.难点:理解负数的意义.【学习过程】生活中的正数与负数议一议:在小学里,我们学过正数、负数、零.你知道右边图片中各数的意义吗?正数与负数的意义像 8848.43、100、357、78 这样的数叫做正数;像-154、-38.87、-117.3、-0.102%这样的数叫做负数.0 既不是正数也不是负数.“+”读作“正”,如“+”读作“正三分之二”,正号通常省略不写;“-”读作“负”,如“-117.3”读作“负一百一十七点三”.例1指出下列各数中的正数、负数:+7,-9,,-4.5,,,.用正数、负数表示相反意义的量C 以上的温度用正数表示,C 以下的温度用负数表示.日常生活中,许多具有相反意义的量都可以用正数、负数来表示.例 2 (1)假如向北走 8km 记作+8km,那么向南走 5km 记作什么?(2)假如粮库运进粮食 3t 记作+3t,那么-4t 表示什么?你还能用正数和负数表示生活中其他意义相反的量吗?整数和分数正整数、负整数、零统称为整数.正分数、负分数统称为分数.Strengthen the team connection, strengthen the knowledge education among the students (especially the first grade students), and promote the formation of good school spirit with the influence of the league members. All League branches should start with recommending outstanding students as the development objects of the League, take am...