A box contains 3 orange balls, 3 green balls and 2 blue balls. Three balls are drawn at random from the box without replacement. The probability of drawing 2 green balls and one blue ball is

Probability of drawing 2 green balls and one blue ball
$= {P_G} \cdot {P_G} \cdot {P_B} + {P_B} \cdot {P_G} \cdot {P_G} + {P_G} \cdot {P_B} \cdot {P_G}$

$= \frac{3}{8} \cdot \frac{2}{7} \cdot \frac{2}{6} + \frac{2}{8} \cdot \frac{3}{7} \cdot \frac{2}{6} + \frac{3}{8} \cdot \frac{2}{7} \cdot \frac{2}{6}$

$= \frac{1}{{28}} + \frac{1}{{28}} + \frac{1}{{28}} = \frac{3}{{28}}$