3x - 2 : 7/2= 4/21 : 1/12

Lời giải:

\((3x - 2):\frac{7}{2} = \frac{4}{{21}}:\frac{1}{{12}}\)

\((3x - 2)\,\,.\,\,\frac{2}{7} = \frac{4}{{21}}\,\,.\,\,12\)

\((3x - 2)\,\,.\,\,\frac{2}{7} = \frac{{16}}{7}\)

\((3x - 2) = \frac{{16}}{7}:\frac{2}{7}\)

3x – 2 = 8

3x = 10

\(x = \frac{{10}}{3}\).

Vậy \(x = \frac{{10}}{3}\).