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 1 of 7.
Ram reddy said:
1 decade ago
Please tell me any other method.
Srinivas said:
1 decade ago
Hi sir, i am little bit poor in maths, what is the meaning of prime numbers...
{ (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) }
Why do choose those no only ?
Why don't you choose (6,6) (2,2)n etc
{ (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) }
Why do choose those no only ?
Why don't you choose (6,6) (2,2)n etc
Nachiket said:
1 decade ago
Prime number is a number which is divisible by 1 and that number only.
DEBAI said:
1 decade ago
Hi RAM, if you tossed 2 dice then you get total 6x6 ie 36 possible cases (equallay likely cases) the above mentioned 15points are prime nos (2, 3, 5, 7, 11, 13, 17, 19. ) if you add any one out of 15 get prime no. That's all.
Sujatha said:
1 decade ago
Could you please tel me any short methods for Probability?
Harshini said:
1 decade ago
Please tel me where to use permutation and where to use combinations. ?
Prasad said:
1 decade ago
Hey why we cant take (1,3),(2,2,),(3,1)etc we can take others also na?
So please solve this in easy way.
So please solve this in easy way.
Anil singh said:
1 decade ago
Prime number divisible by 1 and that nimber only but in the case (1,4), (1,6) etc divided by other number like 1,2,3
Please explain.
Please explain.
Olamikan adesanmi said:
1 decade ago
No wot they mean is that the sum (total) is a prime number. So as for (1, 4) , (1, 6) , the sum are 5 and 7 which are prime numbers.
Rakesh said:
1 decade ago
Why we not chosen (2, 2) because it also prime number and it divisible by only 2?
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