您好 答案是12 详细解答过程如下：7x÷(2.8×0.6）=507x÷1.68=507x=1.68×507x=84x=12
7x÷（2.8×0.6）=507x÷1.68=507x×1/1.68=50等式两边同时乘以1.687x×1/1.68×1.68=50×1.687x=84 x=12
7x＝50×2.8×0.6x＝30×2.8÷7x＝12
