Aptitude - Probability - Discussion

Both event are independent.

Therefore problem of one event is 1/52 and other is 1/52.

P(e) = 1/52+1/52 = 1/26 is right answer.

Its give or not and so answer will be 1c1 or 1c1/52 = 1/52.

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.

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.

By or we mean either a king of heart or a queen of clubs, so p(king of heart)=1/52=p(queen of clubs) and n(e)=2, So p=2/52=1/26.

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.

In question, the term used is 'or', then how the probability of event became 2. (i.e, n (E) =2) ?

In the question they specified that OR(+) so in the numerator we have 2 only.

Here's a simple way. I hope it helps:

Sample space is 52.

Now, in the entire pack of cards, only two cards satisfy the given condition of being either king of hearts of queen of clubs. Therefore, event space = 2
Probability = S/E = 2/52 = 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.