i dont even have any idea how to start. plz gives some hint.(adsbygoogle = window.adsbygoogle || []).push({});

each Supabrek packet contains a card from a set ofnpicture cards. A packet selected at random has the same prob. of containing any one of thencards.

The Smith family already possessk( < n ) different picture cards. They purchase a few more packets, selected one by one randomly until they find a card that is different from thekcards they already have. If this happens when they bought R packets, show that

P ( R = r ) = { (n-k)/(n) } { (k/n)^(r-1) }

thanks.

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# Homework Help: Quite hard discrete prob. distribution q.

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