+ = | 1- = | 1.4-0.9= | 0.3-0.7= |
| 0.13= | 13÷19= | × = | × = |
0÷ × = | ×50%= | 13.8-6.9-3.1= | × ÷ × = |
解:
+ = , | 1- = , | 1.4-0.9=0.5, | 0.3-0.7=-0.4; |
| 0.13=0.001, | 13÷19= , | × = , | × = ; |
0÷ × =0, | ×50%= , | 13.8-6.9-3.1=3.8, | × ÷ × = . |
分析:0.3-0.7运算的结果是负数;0.13=0.1×0.1×0.1由此求解;0÷
×
根据0除以任何非0的数都得0以及0乘任何数都得0进行计算;13.8-6.9-3.1根据连续减去两个数等于减去这两个数的和简算;
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按照从左到右的顺序计算;其它题目根据运算法则直接求解.点评:本题考查了基本的运算,计算时要细心,注意把结果化成最简分数.
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