Label one disc as “1”, two discs as “2”, three discs as “3”,…., sixty three discs as “63”.
These 1+2+3+...+63 = 2016 labeled discs are put in a box.
Discs are then drawn from the box at random without replacement.
(i) What is the minimum number of discs that must be drawn in order to guarantee drawing at least ten discs with the same label?
(ii) Will the answer change if discs were drawn from the box with replacement?

(In reply to Solution by Jer)

(i). ok

(ii) Yes ok, the actual number is much more difficult to establish, simulation repeated  10^5 times or more  might provide a reasonable average.

568 IMHO is not explained.

Posted by Ady TZIDON on 2016-08-25 13:00:26