Question 1192643: Solve the problem and show the solutions
1. Pair of dice is rolled. What is the probability that the sum of the numbers rolled is either 7 or 11?
2. A pair of dice is rolled. What is the probability that the sum of the numbers rolled is either an even number or a multiple of 3?
Found 2 solutions by ikleyn, Alan3354:
Answer by ikleyn(52781)   (Show Source):
You can put this solution on YOUR website! .
On rolling dice problems see the lesson
- Rolling a pair of fair dice
in this site. You will find there many similar solved problems.
Read it and learn the subject from there. After that, you will be able easy solve such problems
ON YOUR OWN, which is your MAJOR GOAL visiting this forum (I believe).
Also, you have this free of charge online textbook in ALGEBRA-II in this site
- ALGEBRA-II - YOUR ONLINE TEXTBOOK.
The referred lesson is the part of this online textbook under the topic "Solved problems on Probability".
Save the link to this textbook together with its description
Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson
into your archive and use when it is needed.
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Hello, right now I have read the "solution" in the post by Alan.
Without long explanations, his solution and his approach are totally wrong and conceptually incorrect.
The best what you can do with it, is to ignore it for the sake of your mental safety.
Again, read the lesson, which I recommended you in my post above.
// I am very surprised to see this mangled "solution" from Alan.
// It is some kind of misunderstanding from his side . . .
Answer by Alan3354(69443)  (Show Source):
You can put this solution on YOUR website! 1. Pair of dice is rolled. What is the probability that the sum of the numbers rolled is either 7 or 11?
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The possible sums are 2 to 12 inclusive ---> 11 possibilities.
Label the dice A and B:
For a sum of 7:
A B
1 6
2 5
3 4
4 3
5 2
6 1
6 of 11 ---> 6/11
For a sum of 11:
A B
5 6
6 5
2 possibilities ---> 2/11
7 or 11 ---> 8/11
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2. A pair of dice is rolled. What is the probability that the sum of the numbers rolled is either an even number or a multiple of 3?
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Use the same method to find a sum of 2, 4, 6, 8, 10 or 12, or 3, 6, 9 or 12.
Note that 6 & 12 are even and a multiple of 3,
so the sums to find are 2, 3, 4, 6, 8, 9, 10 or 12.
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Ikleyn didn't show where I am wrong.
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