| 8÷30= | 25÷100= | 1-75%= | 15× = | 25× ×0.4= |
| 2÷50%= | ×21= | ÷9= | 200×5%= | ×2= |
8÷30= , | 25÷100=0.25, | 1-75%=0.25, | 15× =18 | 25× ×0.4=5. |
| 2÷50%=4, | ×21=18, | ÷9= , | 200×5%=10, | ×2= . |
分析:分数乘法:分子相乘的积做分子,分母相乘的积做分母;
分数除法:除以一个数等于乘这个数的倒数;
25×
×0.4运用乘法交换律简算;
×2先算乘法,再算加法.点评:本题主要考查了简单的分数计算,计算时要细心,注意把结果化成最简分数.
=
×21=
÷9=
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