Aptitude - Probability - Discussion

Guys, please try my solution.

The formula for probability is :

P(E) = n(E)/n(S).

Here, P(E) = probability of an event.
n(E) = total no.of drawn cards.
n(S) = total no.of cards.

Here, n(E) = 1 = total no.of drawn cards.
( because only one card is drawn from a pack of
52 cards.)
n(S) = 52 = total no.of cards.
(because total no.of cards we have 52.).

Firstly, we will apply this formula for first part of this question, i.e; getting a queen out of 52 cards. (please forget club or heart. Because it is given for confusing us. There is no use of it.).

So, Apply formula :

P(E) = n(E)/n(S).
= 1/52.

Now, we will apply this formula in the second part of the question, i.e; getting a king out of 52 cards.

P(E)= n(E)/n(S).
= 1/52.

Now, in the question, the case is given that : getting a queen or a king. Here 'or' means '+' .

Now we will apply '+' sign between these two cases.

The probability of getting a king or a queen is :

= 1/52 + 1/52.
= 2 * 1/52.
= 2/52.
= 1/26.

Hi everyone, hope this helps you.

There are usually 4 suits of the card and each suit contains 13 cards that make (13 *4 =52).
The 4 suits are named as Club, spade, diamond and hearts. Each suit of cards contains a king and a queen.
Therefore as there are 4 suits, so there are 4 kings and 4 queens.
According to the question, Queen of the club is one of the cards from the suit of clubs and same for the king of hearts.

Therefore the probability for the queen of club or king of hearts is P (A Or B) = P (A) + P (B).

= 1/52 + 1/52 = 2/52 reducing it becomes 1/26. Hope you understand. :)

Most of the people said the answer is 1/26 but they don't understand or read the question carefully. In this question, the statement is clear that a one card is drawn from 52 cards, not 26, so why they, again and again, took sample space 26?

The correct answer is 2/13. Because the probability of getting queen is 4/52 i.e., 1/13 and same for the king of heart 1/13. this is because all the 4 types in the cards have 1 king, 1 Jack, 1 Queen and 1 Ace.

So the heart have its 1 king, 1 Jack, 1 Queen and 1 Ace, Diamond have its own and same for other.

Actually, In this que. we have been asked that from the group of club and heart (13 plus 13 equal to 26) we have to extract only one card,

So that can be a queen of club (1/52) and probability of getting a king from 52 cards is 1/52,

So total probability will be sum of both the terms that is 2/52.

Or simply from 26 cards we have to take one card.

Got it.

@Sonam.

If we take the probability of getting a queen out of 52 cards is 4/52 and probability of getting King is 4/52. That is why the terms Club and heart are useful.

Probability of draw one card N(S)= 52C1,
Probability of queen of club n(E1)=13C1,
Probability of King of Heart n(E2) =13C1,
N(E) ={n(E1)+n(E2)}/n(S),
N(E) = (13+13)/52,
n(P) =1/26.

Hi, if asked as queen of club and king of heart, then can we do in this method
(13/26)*(12/25).

Here 1 queen of club selected so 13/26 and 1 king of heart selected so 12/25 Because already one is selected now they are the remaining.

Total cards 52c1.

So answer would be (13/26)*(12/25).

= 6/25.

So answer is (6/25)/52C1 = 312/25.

The answer is 1/26. The question is what the probability of queen of club & the king of heart. So the queen of the club is only one for that pack of cards. Similarly, the king of the heart is only one So, the total probability is 2.

2/52 = 1/26.

Not mention for club queen and king heart we can use normal method.

We have 1 queen of club and 1 queen of heart so,

[1C1(containing queen of club)+1c1(containing king of heart )]/52C1

[1+1]/52= 2/52=>1/26.


@Sajna. Simply "OR" means "addition" and "AND" means "MULTIPLICATION". Out of 52 cards we have only 1 queen of club and 1 king of heart. [1+1]/52.

@kanan i was thinking same as you 4C1 X 4C1)/52C1

but its only right when they have asked just "queen and king" as there are 4 queen and 4 king but here they have asked "Club queen or Heart King" so there is only one Club queen and one Heart King so it's 1/52+1/52

According to me, the answer should be :: 1/2.

Because, we have total 13 card of club and 13 card of heart in which we have to select either one from them. So the overall conclusion is that:

(13C1 + 13C1) / (52C1) which will give us 1/2.

Correct me if I am wrong.