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If two die, each numbered one through five, are rolled, what is the
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28 Sep 2017, 01:57
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Re: If two die, each numbered one through five, are rolled, what is the
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28 Sep 2017, 05:38
There are a total of 25(5*5) options when you throw 2 die, each numbered one through five. For the sum of the two numbers to be prime, the possibilities are 2,3,5, and 7There is 1 way of getting \(2 : (1,1)\) There are 2 ways of getting \(3 : (1,2),(2,1)\) There are 4 ways of getting \(5 : (1.4),(2,3),(3,2),(4,1)\) There are 4 ways of getting \(7 : (2,5),(3,4),(4,3),(5,2)\) Hence the probability of the sum being a prime number is \(\frac{1+2+4+4}{25} = \frac{11}{25}\) (Option B)
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Re: If two die, each numbered one through five, are rolled, what is the
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28 Sep 2017, 06:12
Bunuel wrote: If two die, each numbered one through five, are rolled, what is the probability that the sum of the two numbers will be prime?
A. 16/25 B. 11/25 C. 8/25 D. 7/25 E. 1/5 Sum of the numbers can be {2, 3, 4, 5, 6, 7, 8, 9, 10} Total Possible outcomes = 5*5 = 25 Favourable outcomes = Sum {2, 3, 5, 7} = 1+2+4+4 = 11 Sum 2 may come in 1 way Sum 3 may come in 2 ways {1, 2} or {2, 1} Sum 5 may come in 4 ways {1,4} {2,3}{3,2}{4,1} Sum 7 may come in 4 ways {3,4} {4,3} {2,5} {5,2} Probability = 11/25 Answer: Option B
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Re: If two die, each numbered one through five, are rolled, what is the
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28 Sep 2017, 07:13
Bunuel wrote: If two die, each numbered one through five, are rolled, what is the probability that the sum of the two numbers will be prime?
A. 16/25 B. 11/25 C. 8/25 D. 7/25 E. 1/5 The answer is 7/25
The prime sum can be 2 ,3 , and 5 For 2 we have only 1 choice (1,1) For 3 we have 2 choices ( 2,1) and (1,2) For 5 also we have 4 choices (2,3) ,(3,2) , (4,1) and (1,4) Favorable outcomes =7 Total number of outcomes =25 Therefor the probability=7/25
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Re: If two die, each numbered one through five, are rolled, what is the
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03 Oct 2017, 09:28
Bunuel wrote: If two die, each numbered one through five, are rolled, what is the probability that the sum of the two numbers will be prime?
A. 16/25 B. 11/25 C. 8/25 D. 7/25 E. 1/5 A prime sum can happen in the following ways: A sum of 2: (1, 1) A sum of 3: (1, 2) and (2, 1) A sum of 5: (1, 4), (4, 1), (2, 3), and (3, 2) A sum of 7: (2, 5), (5, 2), (3, 4), and (4, 3) We observe that there are 11 favorable outcomes out of a total of 5 x 5 = 25 outcomes. Thus, the probability of a prime sum is 11/25. Answer: B
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Re: If two die, each numbered one through five, are rolled, what is the &nbs
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