2 dices are rolled. What is the probability of getting the total score as a prime number?

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08 Aug 2018 Probability

2 dices are rolled. What is the probability of getting the total score as a prime number?

OPtion

1) 4/9
2) 7/18
3) 13/36
4) 1/3
5) 1/2
6) 1/4
7) 5/18
8) 11/36
9) 17/36
10) None of these

Solution

Total number of possible outcomes = 6*6 =36

Number of postive outcomes where sum total is prime = { (1, 1), (1, 2), (1, 4), (1, 6), (2, 1), (2, 3), (2, 5), (3, 2), (3, 4), (4, 1), (4,3),(5, 2), (5, 6), (6, 1), (6, 5) }
Count of such outcomes = 15

Probability =15/36 = 5/12

Option 10)

Correct Option: 10 Best Solution (7)

nivendira   6 years AGO

2 dice 6*6=36 n(S)
n(E)=(1,1),(1,2)(1,4)(1,6)(2,1)(2,3)(2,5)(3,2)(3,4)(4,1)(4,3)(5,2)(5,6)(6,1)(6,5)
n(E)/n(s)=15/36=5/12

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G.S.Kantharao   6 years AGO

No of out comes 36
Required out comes (1,1)(1,2),(1,4),(1,6),(2,1),(2,3),(2,5),(3,2),(3,4)(4,1),(4,3),(5,2),(5,6),(6,1),(6,5)=15
Probability=15/36=5/12
My option is 10👈

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SAYAN CHATTERJEE   6 years AGO

The desired combintions are
1,1
1,2
1,4
1,6
2,1
2,3
2,5
3,2
3,4
4,1
4,3
5,2
5,6
6,1
6,5
So, the no. of combinations are 15
The reqd. Probability is 15/36=5/12.
Option 10.

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Kariamal   6 years AGO

P=p(E)/p(S)
P(S)=36
P(E)={(1,1)(1,2)(1,4)(1,6)(2,1)(2,3)(2,5)(3,1)(3,4)(4,1)(4,3)(5,2)(5,6)(6,1)(6,5)}
P(E)=15
So ans=5/12

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Karan   6 years AGO

Total 15 combinations will give total score as a prime number like 2,3,5,7,11.

Hence probability =15/36=5/12.. none of these

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madhuri banda    6 years AGO

2 : 3 : 5 : 7 : 11
(1,1) (1,2) (2,3) (1,6) (5,6)
(2,1) (3,2) (6,1) (6,5)
(4,1) (5,2)
(1,4) (2,5)
(4,3)
(3,4)

probability = 15/36


= 5/12
option 10)

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mohan raj   6 years AGO

sum must be prime so,the possible sum is 2,3,5,7,11 because they are prime numbers.
total sum on dice can be 2,3,4,5,6,7,8,9,10,11,12
so 5/11 is my answer

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