(i) Number of white balls = 27 – (10 + 2) = 15
P(white ball) = \(\frac{Number\,of\,white\,balls}{Total\,number\,of\,balls}\) = \(\frac{15}{27}\) = \(\frac{5}{9}\)
(ii) P (red ball or green ball) = P (red) + P (green)
= \(\frac{10}{27}+\frac{2}{27}\) = \(\frac{12}{27}\) = \(\frac{4}{9}\) .