Question

tìm x biết

\(\frac{x-2010}{12}\) + \(\frac{x-2010}{20}\)+ \(\frac{x-2010}{30}\)+ \(\frac{x-2010}{42}\)+ \(\frac{x-2010}{56}\)+ \(\frac{x-2010}{72}\)= \(\frac{16}{9}\)

Answer 1

mk nghĩ đây là toán 8.

\(Pt\Leftrightarrow\left(x-2010\right)\left(\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+....+\frac{1}{72}\right)=\frac{16}{9}\Leftrightarrow\left(x-2010\right)\left(\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+....+\frac{1}{8.9}\right)=\frac{16}{9}\Leftrightarrow\left(x-2010\right)\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+....-\frac{1}{9}\right)=\frac{16}{9}\Leftrightarrow\left(x-2010\right).\frac{2}{9}=\frac{16}{9}\Leftrightarrow x-2010=8\Leftrightarrow x=2018.\text{ Vậy: x=2018}\)