1/9-5/12×4/5÷3怎么用递等式算?

急~

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1/9-5/唯昌12×4/5÷3
=1/9-1/正闷3÷3
=1/9-1/3×1/3
=1/9-1/指清扒9
=0

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解扒笑：原式=1/9-1/3÷3
=1/9-1/晌粗3×1/宴此镇3
=1/9-1/9
=0

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