Respuesta :
If an experiment has [tex]N[/tex] possible outputs, each with probability
[tex] P_1,\ P_2,\ldots,\ P_N [/tex]
then the sum of all probabilities is always one:
[tex] P_1 + P_2 + \ldots + P_N=1 [/tex]
So, in your case, you have
[tex] P(\text{grape}) + P(\text{cherry}) + P(\text{orange}) = 1 [/tex]
plugging in the given values:
[tex] \dfrac{3}{8} + \dfrac{1}{3} + P(\text{orange}) = 1 \iff \dfrac{17}{24} + P(\text{orange}) = 1[/tex]
we can deduce that
[tex] P(\text{orange}) = 1-\dfrac{17}{24} = \dfrac{7}{24}[/tex]