Question:
A bag contains 4 white and 5 blue balls. They are mixed thoroughly and one ball is drawn at random. What is the probability of getting
(i) a white ball?
(ii) a blue ball?
Solution:
Total number of balls $=4+5=9$
(i) Number of white balls $=4$
$\therefore \mathrm{P}_{(\text {white ball })}=\frac{4}{9}$
Number of blue balls $=5$
$\therefore \mathrm{P}_{\text {(blue ball) }}=\frac{5}{9}$