Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 13)
13.
Two cards are drawn together from a pack of 52 cards. The probability that one is a spade and one is a heart, is:
Answer: Option
Explanation:
Let S be the sample space.
| Then, n(S) = 52C2 = | (52 x 51) | = 1326. |
| (2 x 1) |
Let E = event of getting 1 spade and 1 heart.
 n(E) |
= number of ways of choosing 1 spade out of 13 and 1 heart out of 13 |
| = (13C1 x 13C1) | |
| = (13 x 13) | |
| = 169. |
| P(E) = |
n(E) | = | 169 | = | 13 | . |
| n(S) | 1326 | 102 |
Discussion:
42 comments Page 2 of 5.
Parikshit said:
1 decade ago
The answer should be 13/51.
Both of the following two cases should be considered:
one is spade and the other is heart......and..
one is heart and the other is spade....
so multiply by 2..
Both of the following two cases should be considered:
one is spade and the other is heart......and..
one is heart and the other is spade....
so multiply by 2..
Karim said:
1 decade ago
@Ali, your answer is correct.
The answer should in fact be 13/204 and not 13/102.
You have 13/52 for the first card and for the second it's 13/51.
Multiple together you get 13/204.
The answer should in fact be 13/204 and not 13/102.
You have 13/52 for the first card and for the second it's 13/51.
Multiple together you get 13/204.
(1)
Santosh said:
1 decade ago
Here actually we discussed earlier as both are same combination we add other wise multiply. So clarify that doubt. I understood this problem but add and multiply explain.
Kalai said:
6 years ago
Actually answer 13/102 is correct.
Because you can possible to divide it(169/1326)using by 13.
13*13 = 169.
13*102=1326, So, the answer is 13/1326.
Because you can possible to divide it(169/1326)using by 13.
13*13 = 169.
13*102=1326, So, the answer is 13/1326.
Deepika said:
2 years ago
We have only 4 hearts in total in a deck of 52 cards. So, shouldn't it be 4C1? Why are we using 13C1 for hearts?
Someone, please explain.
Someone, please explain.
(2)
Anamika said:
1 decade ago
The probability of getting spades and hearts why not 26C52+26C51. Because spades and hearts may be from red and black colours of cards.
Xyz said:
1 decade ago
@ kavita:
in case of "AND" we have to "multiply"
& in case of "OR" we have to "Add"
in case of "AND" we have to "multiply"
& in case of "OR" we have to "Add"
Sudhakar said:
6 years ago
How to get 102?
The probability of cards 52C2=52*51/2*1 = 1326.
The cards spade and heart 13C1*13C1 = 169.
169/1326 = 13/12.
The probability of cards 52C2=52*51/2*1 = 1326.
The cards spade and heart 13C1*13C1 = 169.
169/1326 = 13/12.
(1)
Dhruvil said:
1 decade ago
Probability = (13+13)/(52*51) = 26/(52*51) = 1/102.
As there are 13 spade cards and 13 heart cards in each pack of 52 cards.
As there are 13 spade cards and 13 heart cards in each pack of 52 cards.
ARNAV said:
4 years ago
The answer over here is wrong.
As it is mentioned we should be adding.
(13c1+13c1) / 52c2.
=1/51=> is the correct answer.
As it is mentioned we should be adding.
(13c1+13c1) / 52c2.
=1/51=> is the correct answer.
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