= | = | 3× ÷ ×3= | 4.6- = |
| 8.7-6.52= | 12.5×32×2.5= | 13-2.73-5.27= | 7.3÷0.01= |
解:
= , | = , | 3× ÷ ×3=9, | 4.6- =4, |
| 8.7-6.52=2.18, | 12.5×32×2.5=1000, | 13-2.73-5.27=5, | 7.3÷0.01=730. |
分析:3×
÷
×3先把除法变成乘法,再运用乘法结合律简算;12.5×32×2.5先把32分解成8×4,再运用乘法结合律简算;
13-2.73-5.27根据减法的性质简算;
其它题目根据运算法则直接求解.
点评:口算题目要求快速准确,能运用简算方法的要简算.
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