SOLUTION: a fair dice with faces 1,2,3,4,5,6 is rolled twice.find the probability of obtaining a total score of (a)8 or 11 (b)at least 3

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Question 1159223: a fair dice with faces 1,2,3,4,5,6 is rolled twice.find the probability of obtaining a total score of (a)8 or 11 (b)at least 3
Answer by ikleyn(52824) About Me  (Show Source):
You can put this solution on YOUR website!
.

When a fair dice is rolled twice, there are 6*6 = 36 different possible outcomes (pairs of positive integer 
numbers (a,b), where "a" and "b" are from 1 to 6, inclusive).


These outcomes have the same probability  1%2F36  each.


The sum of 8 have these 5 outcomes

    (2,6), (3,5), (4,4), (5,3), (6,2).



The sum of 11 have these 2 outcomes

    (5,6), (6,5).



Therefore,  P(8 or 11) = P(8) + P(11) = 5%2F36 + 2%2F36 = 7%2F36.



It is the answer to part (a).

Solved.

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Regarding part  (b),  let me tell you that I don't like  VERY  MUCH  to have more that one question in the post.

It is because  I  DON'T  WANT  my response becomes a mess.

Make your conclusion/conclusions . . .


Also,  I firmly believe,  that,  when the visitor put many question in his  (or her)  post,  it only means
that the visitor does not want to learn the subject,  at all;  it only means that the visitor wants
the tutors work  INSTEAD  of  HIM  (or  HER).

Therefore,  I always say that those who put more than one problem/question into the post,  work  AGAINST  their own interests.