解:X/1.2=90+(X-90)/1.3方程两边同时乘以1.56,得:1.3X=140.4+1.2(X-90)1.3X=140.4+1.2X-1081.3X-1.2X=140.4-1080.1X=32.4X=324很高兴为你解答,有问题可随时问我,满意的话望采纳哦(谢谢),祝开心~