Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,市一小五数组,课前铺垫,看谁算得快,0.32100,24,0.24,15,0.15,0.40.5,1.258,2.54,0.245,0.60.1,=,32,=24.24,=14.85,=0.2,=10,=10,=1.2,=0.06,0.50.2=500.2=5000.2=,0.1,10,100,2.50.4,=,1,0.2540,=10,1.250.8,=1,1.2580,=100,2,、在括号里填上适当的数。,(1)0.32=4()(2)1.02=1+(),(3)0.99=1-()(4)9.8=()-(),0.08,10,0.01,0.02,0.2,4.21.69,2.50.770.4,（,）,6.13.6+3.93.6,（）,填一填,1.69,4.2,2.5,0.4,0.77,6.1,3.9,3.6,3,、乘法有哪些运算定律？,怎样用字母式子表示？,乘法交换律：,ab=ba,乘法结合律：,(a,b),c=a,(b,c),乘法分配律：,(a+b),c=a,c+b,c,学习目标：,1、能正确的进行小数乘法的简,便运算。,2、能根据不同题型，灵活的进行简便计算。,揭题示标,比一比,看谁算得巧,(234)15,25734,10232,=25473,=,100,73,=7300,=23(415),=23,60,=1380,=(,100,+2)32,=10032+232,=3200+64,=3264,基础练习,练 一 练,7.60.8+0.27.6,0.2536,0.8599,0.25321.25,=7.6,(0.8+0.2),=7.61,=7.6,=0.25,49,=19,=9,=0.85,(,100-1,),=0.85100-0.851,=85-0.85,=84.15,=0.25,48,1.25,=,(,0.254,),(,8 1.25,),=110,=10,练 一 练,0.258.54,1.288.6+0.728.6,=0.2548.5,=18.5,=8.5,=(1.28+0.72)8.6,=28.6,=17.2,0.42160+361.6-34 3.2,5.4450+4645,拓展巩固,通过本节课的学习，你有哪些新的收获？,小数计算应注意的问题：,一审：审清题目。,二看：观察数字特征，选择合理的运算律。,三算：认真计算。,四查：查运算顺序；查数字；查每一步的计算。,4.53.6-3.64.1,（）,4,=4.504.1,=1.8-0.254,=0,=1.8-1,=0.8,数学医院,当堂检测,(,),(,),(1)0.0340.50.8,(2)0.1256.80.8,(3)2.80.25,下面各题怎样计算简便就怎样算,.,（5）760.08+0.27.6,（4）0.8599+0.85,=,7.60.8,+0.27.6,=7.6(0.8+0.2),=7.61,=7.6,=0.8599+,0.851,=0.85(99+1),=0.85100,=85,