Open In App

ISRO | ISRO CS 2017 | Question 3

Like Article
Like
Save
Share
Report

A bag contains 19 red balls and 19 black balls. Two balls are removed at a time repeatedly and discarded if they are of the same colour, but if they are different, black ball is discarded and red ball is returned to the bag. The probability that this process will terminate with one red ball is

(A) 1
(B) 1/21
(C) 0
(D) 0.5


Answer: (A)

Explanation: Possible outcomes: RR, BB, RB and BR. If two same coloured balls appear both are discarded whereas if different coloured balls appear only black ball is discarded. Black balls will always be used up and 1 red ball will remain at the end regardless of the outcome of the experiment. The probability that this process will terminate with one red ball is always 1.

Option (A) is correct.


Quiz of this Question


Last Updated : 14 Mar, 2018
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads