Q. 164.5( 4 Votes )

# Two cards are dra

Answer :

Note: While reading this question you might have observed that cards are being drawn successively and sometimes in other question you might have get cards are drawn simultaneously

You have to be careful regarding these two words while solving the question. Both have a different meaning.

E.g.:-

When you draw 3 cards out of 52 simultaneously, then total no of ways of drawing is simply 52C_{3} = 22100. You draw 3 cards at a time.

When you draw 3 cards out of 52 successively, then total no of ways of drawing is not simply 52C_{3}, once you have drawn the first card, only 51 cards are remaining and so on. You are drawing only one card at a time

In such case total ways of drawing 3 cards = 52C_{1} × 51C_{1} × 50C_{1 =} 132600

Hence both are entirely different. So Be cautious regarding it.

Let’s solve the problem now:

Note: In our problem, it is given that after every draw, we are replacing the card. So our sample space will not change

In a deck of 52 cards, there are 4 kings each of one suit respectively.

Let X be the random variable denoting the number of kings for an event when 2 cards are drawn successively.

∴ X can take values 0, 1 or 2

P(X = 0) =

{As we have to select 1 card at a time such that no king is there so the first probability is 48/52 and as the drawn card is replaced, next time again probability is 48/52 }

Similarly, we proceed for other cases.

P(X = 1) =

{we might get a king in the first card or second card, so both probabilities are added}

Similarly,

P(X = 2) =

Now we have p_{i} and x_{i.}

∴ Now we are ready to write the probability distribution for X:-

The following table gives probability distribution:

Rate this question :

An urn contains 3Mathematics - Board Papers

Two cards are draMathematics - Board Papers

There are three cMathematics - Board Papers

Three numbers areMathematics - Board Papers

Let <span lang="EMathematics - Board Papers

Which of the follRD Sharma - Volume 2

Which of the follRD Sharma - Volume 2

A random variableRD Sharma - Volume 2