ISI 2009

Posted by Ram on Mar 31, 2012; 5:41am
URL: http://discussion-forum.276.s1.nabble.com/ISI-2009-tp7423881.html

1. Two persons, A and B, make an appointment to meet at the train station
between 4 P.M. and 5 P.M.. They agree that each is to wait not more than 15
minutes for the other. Assuming that each is independently equally likely to
arrive at any point during the hour, find the probability that they meet.
A. 15/16
B. 7/16
C. 5/24
D. 22/175


3. A box contains 100 balls. Some of them are white and the remaining are
red. Let X and Y denote the number of white and red balls respectively. The
correlation between X and Y is
A 0.
B 1.
C −1.
D some real number between −1/2 and 1/2