Summary: HOMEWORK SOLUTIONS FOR MATH 5651
HOMEWORK FOR WEEK 10 OF SPRING 2011
Text: de Groot and Schervish, 4th edition
Assignment: §5.3: 3,4,5; §5.4: 3,6,7,12,14; §5.5: 2,3,6; §5.6: 2,7,9,11,13
Problem 3 of §5.3
Let X be the number of red balls in the sample of 7 balls without replacement
taken from a box containing 5 red balls and 10 blue balls. Then X is hypergeomet-
rically distributed with parameters A = 5, B = 10, and n = 7, and hence
EX = 7 ·
5
15
=
7
3
, Var(X) = 7 ·
5
15
10
15
15 - 7

Source: Anderson, Greg W. - School of Mathematics, University of Minnesota

Collections: Mathematics