Stat 400 In Class Worksheet 3 Answers
T.A. Emily King
February 20, 2008
1. (Book p 89 #2)
•Consider the next baby born in a hospital. Let Xbe the r.v. taking
the values {0 if the next baby is a boy,1 if the next baby is a girl}.
•Consider the outcome of a spin of the roulette wheel Let Xbe the r.v.
taking the values {0 if it doesn’t land on 00,1 if if it does land on 00}.
•Suppose that a student randomly shows up at a professor’s office. Let
Xbe the r.v. taking the values {0 if the professor isn’t there,1 if the professor is there}.
•Etc.
2. (Modified from book p 90 #4) The possible values of Xare {0,1,2,3,4,5}.
The outcomes 90210, 20770 and 20740 would all yield the Xvalue 2.
3. (Book p 90 #6) The possible values of Xare {1,2,3, . . .}. Here is a listing
of some pairs of outcomes and their associated Xvalues:
X Outcome
1 L
2 AL, RL
3 AAL, ARL, RAL, RRL
4 AAAL, AARL, ARAL, RAAL, RRAL, RARL, ARRL, RRRL
5 AAAAL, AAARL, . . ., RRRRL
4. (Book p 98 #11ac) In solutions manual.
5. (Book p 99 #21) In solutions manual.