probabbility

Question

Answer 1

Total sample space = select one ball from each box=$\binom{6}{1} + \binom{9}{1} +\binom{12}{1}$ = 648

Let all ball of color White = $\binom{1}{1} + \binom{2}{1} +\binom{3}{1}$= 6

Let all ball of color Red = $\binom{3}{1} + \binom{3}{1} +\binom{4}{1}$= 36

Let all ball of color Black =$\binom{2}{1} + \binom{4}{1} +\binom{5}{1}$= 40

Total events = 6 + 36 + 40 = 82

Probability = $\frac{82}{648}$