计算x+30%x=52；50%x+30=31.5；1112x+37%=1；x-55%=1.8．

Question

计算
x+30%x=52；          50%x+30=31.5；           (11)/(12)x+37%=1；             x-55%=1.8．

Answer 1

（1）x+30%x=52
           1.3x=52
      1.3x÷1.3=52÷1.3
              x=40

（2）50%x+30=31.5
  0.5x+30-30=31.5-30
        0.5x=1.5
     0.5x×2=1.5×2
           x=3

 （3）(11)/(12)x+37%=1
(11)/(12)x+0.37-0.37=1-0.37
          (11)/(12)x=0.63
      (11)/(12)x×(12)/(11)=0.63×(12)/(11)
             x=(189)/(275)

 （4）x-55%=1.8
x-0.55+0.55=1.8+0.55
          x=2.35