Christmas 4

There are only 3 packages left under the tree - two for Julka and one for Zuzka. Julka took two at once. What is the probability that both belong to her?

Correct answer:

p =  0.3333

Step-by-step explanation:

$$\begin{gathered} C_1(3)=\left(\genfrac{}{}{0ex}{}{3}{1}\right)=\frac{3!}{1!(3-1)!}=\frac{3}{1}=3 \\ {n}_1=\left(\genfrac{}{}{0ex}{}{3}{1}\right)=3 \\ {n}_2=1 \\ p=\frac{n_2}{n_1}=\frac{1}{3}=0.3333 \end{gathered}$$

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