On the fifth day of Christmas, Calvin gave to me

Discrete Mathematics Level 2

5 golden rings

At the registry of marriage, there were 5 couples (total of 10 people) that were waiting to get married. If we pick any two people out of these 10, what is the probability that they are a couple?

1) \( \frac{1}{5} \)
2) \( \frac{ 1}{9} \)
3) \( \frac{1}{10} \)
4) \( \frac{1}{45} \)

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