Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 10)
10.
Two dice are tossed. The probability that the total score is a prime number is:
Answer: Option
Explanation:
Clearly, n(S) = (6 x 6) = 36.
Let E = Event that the sum is a prime number.
| Then 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) = 15.
| P(E) = |
n(E) | = | 15 | = | 5 | . |
| n(S) | 36 | 12 |
Discussion:
64 comments Page 5 of 7.
Rakesh said:
1 decade ago
Why we not chosen (2, 2) because it also prime number and it divisible by only 2?
Shikha Patel said:
9 years ago
Thanks @Azly.
By using axis method, we can easily solve the question like this.
By using axis method, we can easily solve the question like this.
Harshini said:
1 decade ago
Please tel me where to use permutation and where to use combinations. ?
Sowmya said:
1 decade ago
The sample space is a set, so repeated event (1, 1) is taken only once.
Nachiket said:
1 decade ago
Prime number is a number which is divisible by 1 and that number only.
Karma said:
8 years ago
Here, I used nCr. But its not working, why?
Can anyone explain me.
Can anyone explain me.
Abhilasha said:
9 years ago
@Vipin.
2 is also a prime number that's the reason we take (1,1).
2 is also a prime number that's the reason we take (1,1).
Maths said:
3 years ago
1 is not a prime number.
So, the correct answer is 14/36 = 7/18.
So, the correct answer is 14/36 = 7/18.
Mirekua said:
8 years ago
Please, from where E={(1,1),(1,2)...} is came? Please explain.
Mahendra said:
8 years ago
Why we enter prime numbers sum as 15? Please explain the step.
(1)
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