Extra Problems From Ch. 2
1) Do part (b) of Problem 21 on p. 52 of Ross for the case of i = 3 (and only for the case of i = 3).
Consider all of the children from all of the families, and suppose that each child is just as likely to be selected as any of the other children.)
Provide a brief written explanation to indicate
how you arrived at your final answer. (Be careful; the answer is not 5/20 = 1/4. (5/20 = 1/4 is the answer for part (a)
of this problem for the case of i = 3.))
2) Do part (a) of Problem 28 on p. 52 of Ross. Assume the balls are drawn without replacement (i.e., a subset of three different balls from the
19 will be drawn). Don't do the sampling with replacement variation that is described after part (b) of the problem.
Show adequate work
to justify your answer (which should be given as a number (and not left in terms of factorials, binomial coefficients, etc.)).
3) Do part (a) of Problem 35 on p. 53 of Ross. Assume the balls are drawn without replacement (i.e., a subset of seven different balls from the
46 will be drawn). (Don't consider sampling with replacement.)
While you don't have to provide a detailed justification for your
answer (which should be given as a number (and not left in terms of factorials, binomial coefficients, etc.)), you should provide
an expression which indicates where your final answer comes from.
4) Do part (a) of Problem 43 on p. 53 of Ross.
Provide adequate justification for your answer (which should be given as a function of N which is simplified as much as possible).
Make the usual assumptions (i.e., suppose that all possible arrangements of the people in a line are equally likely).