Question

15．解方程：$\frac{0.2x-0.1}{0.3}$-$\frac{100x+10}{120}$=$\frac{0.02+0.01}{0.04}$-2．

Answer 1

分析 关键分数的基本性质把$\frac{0.2x-0.1}{0.3}$、$\frac{100x+10}{120}$、$\frac{0.02+0.01}{0.04}$用进行化简．然后再进行解答方程即可．

解答 解：$\frac{0.2x-0.1}{0.3}$-$\frac{100x+10}{120}$=$\frac{0.02+0.01}{0.04}$-2
         $\frac{2x-1}{3}$-$\frac{10x-1}{12}$=$\frac{3}{4}$
        $\frac{8x-4}{12}-\frac{10x-1}{12}$=$\frac{3}{4}$
               $\frac{18x-5}{12}$=$\frac{3}{4}$
               72x-20=36
            72x+20-20=36+20
               72x÷72=56÷72
                     x=$\frac{7}{9}$

点评 本题运用等式的性质进行解答即可，解答过程中注意等于号要对齐．