We have the Word COCONUT and the word CHOCOLATE as we can see the common letter in the word are C, O, T
The probability to obtain a letter that in the word Chocolate is
[tex]P(\text{letter in the word chocolate)=P(C)+P(O)+P(T)}[/tex]where
[tex]\begin{gathered} P(C)=\frac{2}{7} \\ P(O)=\frac{2}{7} \\ P(T)=\frac{1}{7} \end{gathered}[/tex]then we substitute this information
[tex]P(\text{letter in the word chocolate)=}\frac{2}{7}+\frac{2}{7}+\frac{1}{7}=\frac{5}{7}[/tex]The probability to chose a card that it will be a letter in the word CHOCOLATE is 5/7
