直接写出得数
+ = | - = | 12× = | ×14= | 20÷ = |
× = | 0× = | ÷ = | ÷ ×12= | 14× ÷14× = |
解:
+ = , | - = , | 12× =9, | ×14=4, | 20÷ =45, |
× = , | 0× =0, | ÷ = , | ÷ ×12=9, | 14× ÷14× = . |
分析:分出加减法:先通分变成同分母的分数再计算;
分数乘法:分子与分子相乘的积做分子,分母与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;由此求解.
点评:本题考查了分数的计算,运用运算法则求解,注意把结果化成最简分数.
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