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题目:计算:0.8×2/11+4.8×(-2/7)-2.2÷3/7+0.8×9/11

问题描述:

0.8×2/11+4.8×以括号-2/7括号减2.2÷3/7+0.8×9/11



最佳答案:

解:

0.8×2/11+4.8×(-2/7)-2.2÷3/7+0.8×9/11

=1.6/11-28.8/21-2.2/21+7.2/11

=8.8/11-31/21

=0.8-31/21

=16.8/21-31/21

=-14.2/21

=-71/105


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