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9.8×65.2×1.25-12.5×0.652×188(x-2)=2(x+7)611×7-12×311(22+6):7=(A-6):960%:90%=A:112规定a◇b=(a+b)÷b,已知m◇(4◇2)=1.2,求m的值.

题目详情
9.8×65.2×1.25-12.5×0.652×18
8(x-2)=2(x+7)
6
11
×7-12×
3
11

(22+6):7=(A-6):9
60%:90%=A:
1
12

规定a◇b=(a+b)÷b,已知m◇(4◇2)=1.2,求m的值.
▼优质解答
答案和解析
(1)9.8×65.2×1.25-12.5×0.652×18,
=9.8×6.52×12.5-12.5×6.52×1.8,
=6.52×12.5×(9.8-1.8),
=6.52×12.5×8,
=6.52×100,
=652;

(2)8(x-2)=2(x+7),
  8(x-2)÷2=2(x+7)÷2,
     4(x-2)=x+7,
         4x-8=x+7,
       4x-8+8=x+7+8,
           4x=x+15,
         4x-x=x+15-x,
           3x=15,
        3x÷3=15÷3,
            x=5;

(3)
6
11
×7-12×
3
11

=
6
11
×7-6×
6
11

=(7-6)×
6
11

=
6
11


(4)(22+6):7=(A-6):9,
           28:7=(A-6):9,
      7×(A-6)=28×9,
           7A-42=252,
        7A-42+42=252+42,
              7A=294,
           7A÷7=294÷7,
               A=42;

(5)60%:90%=A:
1
12

         0.9A=0.6×
1
12

     09A÷0.9=
1
20
÷0.9,
            A=
1
18


(6)4◇2=(4+2)÷2=6÷2=3;
m◇3=(m+3)÷3;
因此(m+3)÷3=1.2,
(m+3)÷3×3=1.2×3,
          m+3=3.6,
        m+3-3=3.6-3,
            m=0.6.
答:m的值是0.6.