解方程.(1)60%X+25=40     (2)X+12.5%X=72 (3)75%X-116=

2025-01-24 13:34:55
推荐回答(1个)
回答1:

(1)60%X+25=40,
      60%X+25-25=40-25,
            60%x=15,
       60%x÷60%=15÷60%,
               x=25;

(2)X+12.5%X=72,
       1.125x=72,
1.125x÷1.125=72÷1.125,
            x=64;

(3)75%X-

1
16
=0.5X,
 75%X-
1
16
+
1
16
=0.5X+
1
16

    75%x-0.5x=0.5x+
1
16
-0.5x,
        0.25x=
1
16

  0.25x÷0.25=
1
16
÷
0.25,
            x=
1
4


(4)X×(1-25%-20%)=550,
                 55%x=550,
            55%x÷55%=550÷55%,
                    x=1000.