四年级下册数学小数除法简便计算例题解析

四年级下册数学小数除法简便计算例题解析


简介:
①a÷b÷c=a÷(b×c) 3.52÷2.5÷0.4 =3.52÷(2.5×0.4) =3.52÷1 =3.52 ②a÷(b×c)=a÷b÷c 3.9÷(1.3×5) =3.9÷1.3÷5 =3÷5 =0.6 ③(a±b)÷c=a÷c±b÷c 150.15÷1.5 =(150+0.15)÷1.5 =150÷1.5+0.15÷1.5 =100+0.1 =100.1 ④a÷c±b÷c=(a±b)÷c 27÷4.5+18÷4.5 =(27+18)÷4.5 =45÷4.5 =10 ⑤a÷(b÷c)=a÷b×c 3.9÷(1.3÷5) =3.9÷1.3×5 =3×5 =15 ⑥a÷b×c=a÷(b÷c) 16.8÷4.8×2.4 =16.8÷(4.8÷2.4) =16.8÷2 =8.4 ⑦a×(b÷c)=a×b÷c 8×(12.5÷2) =8×12.5÷2 =100÷2 =50 ⑧a×b÷c=a×(b÷c) 3.9×7.6÷3.8 =3.9×(7.6÷3.8) =3.9×2 =7.8