In: Math
Two 6-sided dice are rolled. Let X be the larger of the two numbers showing. For each i from 1 to 6, find the probability that X = i.
Solution:
Given: Two 6-sided dice are rolled.
X = the larger of the two numbers showing.
For example: ( 2 , 1 ) then X = 2
( 3 , 3 ) , then X = 3
and so on.
Sample space of rolling of two dice is:
We have numbers from 1 to 6 on each die, then minimum possible value for X is 1 and maximum possible value would be 6.
Now we need to find counts for each largest number.
X=i | Outcomes: | f : frequency | Calculations: | P(X=i) |
---|---|---|---|---|
1 | (1,1) | 1 | =1/36 | 0.0278 |
2 | (1,2) , (2,2) , (2,1) | 3 | =3/36 | 0.0833 |
3 | (1,3) , (2,3) , (3,3 ), (3,2 ), (3,1) | 5 | =5/36 | 0.1389 |
4 |
(1,4) , (2,4) , (3,4 ), (4,4 ) , (4, 3 ), (4, 2) ,(4 , 1) |
7 | =7/36 | 0.1944 |
5 |
(1,5) , (2,5) , (3,5 ), (4,5 ) ,(5,5 ) , (5, 4 ), (5, 3) ,(5 ,2), (5,1) |
9 | =9/36 | 0.2500 |
6 |
(1,6) , (2,6) , (3,6 ), (4,6 ) ,(5,6 ) ,(6,6) , (6, 5 ), (6, 4) ,(6,3) , (6 ,2), (6,1) |
11 | =11/36 | 0.3056 |
N = 36 |