解方程78-3x=111614+34x=1236：x=54：334x-2.5=553%x-36%x=51．

Question

解方程
(7)/(8)-3x=(11)/(16)         
(1)/(4)+(3)/(4)x=(1)/(2)     
36：x=54：3
(3)/(4)x-2.5=5               
53%x-36%x=51．

Answer 1

①(7)/(8)-3x=(11)/(16) 
  (14)/(16)+3x-3x=(11)/(16)+3x
 (11)/(16)+3x−(11)/(16)=(14)/(16)−(11)/(16)
        3x=(3)/(16)
     3x×(1)/(3)=(3)/(16)×(1)/(3)
         x=(1)/(16)

        
 ②(1)/(4)+(3)/(4)x=(1)/(2) 
(1)/(4)−(1)/(4)+(3)/(4)x=(2)/(4)−(1)/(4)
     (3)/(4)x=(1)/(4)
 (3)/(4)x×(4)/(3)=(1)/(4)×(4)/(3)
      x=(1)/(3)

    
③36：x=54：3
    54x=108
54x÷54=108÷54
      x=2


  ④(3)/(4)x-2.5=5   
(3)/(4)x+2.5-2.5=5+2.5
      0.75x=7.5
0.75x÷0.75=7.5÷0.75
          x=10
            
⑤53%x-36%x=51
      0.17x=51
0.17x÷0.17=51÷0.17
          x=300