Round destiny

There are five white and ten red balls in the destiny. Four balls will be drawn at random. What is the probability of the event "at least two spheres are white"?

Correct answer:

p =  0.8352

Step-by-step explanation:

$$\begin{gathered} p_1=5/15\cdot 10/14\cdot 9/13\cdot 8/12=\frac{10}{91}\doteq 0.1099 \\ {p}_2=5/15\cdot 4/14\cdot 10/13\cdot 9/12=\frac{5}{91}\doteq 0.0549 \\ p=1-(p_1+p_2)=1-(0.1099+0.0549)=0.8352 \end{gathered}$$

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