\[\boxed{\mathbf{289.}}\]
\[N = 24;\ \ К = 13;\ \ З = 5.\]
\[24 - 13 - 5 = 6 - синих\ \]
\[авторучек.\]
\[\textbf{а)}\ Р(К) = \frac{К}{N} = \frac{13}{24}.\]
\[\textbf{б)}\ Р(В) = \frac{К + С}{N} = \frac{13 + 6}{24} = \frac{19}{24}.\]
\[\textbf{в)}\ Р(Д) = \frac{С + З}{N} = \frac{6 + 5}{24} = \frac{11}{24}.\]
\[\textbf{г)}\ Р(Е) = \frac{К + С}{N} = \frac{13 + 6}{24} = \frac{19}{24}.\]