Probability question, please help :)
Join Date: May 2015
Posts: 415
Hi there,
Hoping someone with some math skills can help me calculate the following.
We have 10 cards, every time we draw 1 card at random, we keep drawing cards until we have completed the set of 10 cards.
How many draws do we need on average to complete all 10 cards?
Thanks!
Join Date: May 2015
Posts: 415
NVM, got it figured out
Thread can be closed
Join Date: Mar 2009
Posts: 5,935
If you didn't already, see the Coupon Collector problem.
Join Date: May 2015
Posts: 415
Thanks! was not aware of the Coupon Collector problem, but used basically the same formula to get my answer, for anyone who wonders its 29.28.
Join Date: Aug 2002
Posts: 17,082
You can get close with simple estimates. Each card is about even money to be picked in about 7 tries. Thus about 15/16 in 28. The chances that there are no failures in 28 tries among the ten cards is about 15/16 to the tenth power which is about one half.