解方程. 500÷125+0.6x=4 1/3×(x+2/5)=1 44.8÷2x=56.

问题描述:

解方程.
500÷125+0.6x=4

1
3
×(x+
2
5
)=1
44.8÷2x=56.

(1)500÷125+0.6x=4
               4+0.6x=4
             4+0.6x-4=4-4
                 0.6x=0
                    x=0;
(2)

1
3
×(x+
2
5
)=1
 
1
3
×(x+
2
5
)×3=1×3
            x+
2
5
=3
         x+
2
5
-
2
5
=3-
2
5

              x=2
3
5

(3)44.8÷2x=56
44.8÷2x×2x=56×2x
       112x=44.8
  112x÷112=44.8÷112
          x=0.4