Example 2 A fair die is tossed twice and the values are observed in order. Let
A={(a,b)|a>=b},B={(a,b)|a=6} and
C={(a,b)||a-b|=2}
(1) Find the probability of each outcome event assuming that all faces values are equally likely.
Decide if
AsubB or
BsubA ?
(- Find a descriptive definition of
A\cup B,A\cap B^(c) and
A^(c).
Find a descriptive definition of
A\cap C.
Solution 2 (1)
S={(a,b)|1<=a,b<=6}. Think of
S as a
6\times 6 matrix, so
A is all terms on or below the diagonal, 21, so
P[A]=23.B is the last row, so
P[B]=(6)/(3), and
C={(3,1),(1,3),cdots,(4,6),(6,4)},8 terms, so
P[C]=(8)/(36).
Parts (2), (3), and (4) are Homework 1.
