Pratham Ashish
Last Activity: 15 Years ago
hi varsha,
since out of 51 cards we checked 13 n all of dem r red, dat means out of d 38 cards, either of d two case may occur, 1.) one red card is missing or 2.) one black is missing
in 1st case, der wud be 26 blacks n 12 red
in 2nd case., der wud be 25 blacks n 13red
in total of 39 cards , der r 38 available n 1 is missing ,
required p = when black is missing/either red or black is missing
p (black is missing) = 26 c 25 * 13 c 13 /( 26 c 25 * 13c 13 + 26c16 * 13 c 12) = dis will give u
p = 2/3