A bag contains 3 red jewels and 7 black jewels. You randomly draw the jewels out one by one without replacement. What is the probability that the last red jewel was the 8th one withdrawn?

A bag contains 3 red jewels and 7 black jewels. You randomly draw the jewels out one by one without replacement. What is the probability that the last red jewel was the 8th one withdrawn?

  • Jewels in the box no balls! Probability 0

  • I see you mistyped balls in the subject, but wrote correctly below

  • You want to find the probability of last red jewel is drawn at the 8th draw?

  • Yes. Typo.

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  • Let me know if you need any clarifications.

  • Wouldn't your solution also include situations that have red jewel behind the 8th? The question asks for possibilities where the last red jewel is the 8th, and no more red jewels behind it.

  • Oh you are right. I misunderstood the question. Will revise my solution soon.

  • I just revised the solution. Sorry for the inconvenience. Let me know if you have any questions.

The answer is accepted.