So 2 dice has been thrown, I will SURELY get 2 on 1 dice. Find the probability that the sum of 2 dices is 5.
Is the answer 1/3 or 1/9?
Is the answer 1/3 or 1/9?
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Two dice are thrown and one of them shows 2.
∴ S = { (1,2),(2,1), (2,2), (2,3),(3,2), (2,4),(4,2), (2,5),(5,2),(2,6),(6,2) }
∴ n(S) = 11
If A : total score is 5, then
A = { (2,3), (3,2) }
∴ n(A) = 2
∴ P(A) = n(A) / n(S) = 2/11 .............. Ans.
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∴ S = { (1,2),(2,1), (2,2), (2,3),(3,2), (2,4),(4,2), (2,5),(5,2),(2,6),(6,2) }
∴ n(S) = 11
If A : total score is 5, then
A = { (2,3), (3,2) }
∴ n(A) = 2
∴ P(A) = n(A) / n(S) = 2/11 .............. Ans.
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You are Welcome, Becky !
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If you are sure to roll a 2 on one of the dice, and you need to reach a sum of 5. Then you will need to roll a 3 on the second dice, which would be a 1 in 6 chance. So in essence you only need a 3. If I am wrong than I don't understand the question, sorry.
The answer is 1/6. You know that one dive will roll a 2, but you need a sum of 5. 2+3=5, so hence the second dice has to roll 3. No other numbers on the second dice can be rolled to get a sum of 5, except 3. A dice has 6 faces, you have a 1 in 6 chance of rolling a 3. I believe the answers you listed are phony.
The answer is 1/6. You know that one dive will roll a 2, but you need a sum of 5. 2+3=5, so hence the second dice has to roll 3. No other numbers on the second dice can be rolled to get a sum of 5, except 3. A dice has 6 faces, you have a 1 in 6 chance of rolling a 3. I believe the answers you listed are phony.