32.8+5.6+7.2 =32.8+7.2+5.6 =40+5.6 =45.6
32.8乘0.2+7.2除以5的简便算法 32.8x0.2+7.2÷5 =32.8÷5+7.2÷
32.8*1.72-0.72*32.8 =32.8x(1.72-0.72) =32.8x1 =
72×8-64×4 =(72-32)×8 =40×8 =320 你好,本题已解答,如果满意
看图
需要化成乘法才可以结算,其他的可以问老师。
47.8-32.2-7.8 =47.8-(32.2+7.8) =47.8-40 =7.8
7.2x0.32÷0.8 = 7.2x(0.32÷0.8) = 7.2x0.4 = 2.88
32.80.2+7.2÷5 =32.80.2+7.20.2 =(32.8+7.2)0
利用乘法结合律。