Tìm x biết: \(\frac{2}{3}x - \frac{1}{2} = \frac{1}{{10}}\)

* Hướng dẫn giải

\(\begin{array}{l}\frac{2}{3}x - \frac{1}{2} = \frac{1}{{10}}\\\,\,\,\,\,\frac{2}{3}x\,\,\,\,\,\,\,\,\,\, = \frac{1}{{10}} + \frac{1}{2}\\\,\,\,\,\,\frac{2}{3}x\,\,\,\,\,\,\,\,\,\, = \,\,\frac{6}{{10}}\\\,\,\,\,\,\frac{2}{3}x\,\,\,\,\,\,\,\,\,\,\, = \frac{3}{5}\\\,\,\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\,\, = \frac{3}{5}:\frac{2}{3}\\\,\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\,\,\, = \frac{9}{{10}}\end{array}\)

Chọn C