课件12张PPT。文具店---Decimal Multiplication北师大版四年级数学下册教学目标本节课我们主要来学习小数乘法,同学们通过对整数乘法的复习来探索小数乘法的计算方法,能够达到独立解决有关小数乘法的实际问题的水平。2.一支圆珠笔 2 元,买 4 支要多少钱?2 × 4 = 2 + 2+ 2 + 2 = 1.oral calculation What information do you know from the ichnography? Can you ask some maths questions? 买 4 块橡皮需要多少元?Do you know how to estimate it?买 4 块橡皮需要多少元?方法二:方法三:方法一:求几个相同加数和的简便运算.0.90.8算一算:0.70.52.41.50.080.564×0.3 = 0.3 ×4你能计算4×0.3吗?与同学交流你的想法。交换两个因数的位置,积不变。0.10.5110比一比,谁最快2.43.52.870.30.360.158.4How do we multiply a decimal by a whole number?we should look at the decimal as a whole number.1.每千克苹果3.2元,妈妈买了3千克,一共要用多少元?解决问题:2.小明每小时走 5千米, 1.5可以走多少千米?3.2 ×3 = 9.6(元)5 ×1.5 = 7.5(千米)