五上数学小数乘除法简便运算解题技巧

五上数学小数乘除法简便运算解题技巧


简介:
一、类型1:一个数除以2、4、8 1、一个数÷2,就等于这个数×0.5 2、一个数÷4,就等于这个数×0.25 3、一个数÷8,就等于这个数×0.125 12.8×0.25+7.2÷4 =12.8×0.25+7.2×0.25 =(12.8+7.2)×0.25 =20×0.25 =5 3.3÷2+6.7×0.5 =3.3×0.5+6.7×0.5 =(3.3+6.7)×0.5 =10×0.5 =5 12.4÷4+87.6×0.25 =12.4×0.25+87.6×0.25 =(12.4+87.6)×0.25 =100×0.25 =25 3.3÷8+6.7×0.125 =3.3×0.125+6.7×0.125 =(3.3+6.7)×0.125 =10×0.125 =1.25