Mathematics Part-II

Book: Mathematics Part-II

Chapter: 13. Probability

Subject: Maths - Class 12th

Q. No. 17 of Exercise 13.4

Listen NCERT Audio Books - Kitabein Ab Bolengi

17

Suppose that two cards are drawn at random from a deck of cards. Let X be the number of aces obtained. Then the value of E(X) is

Given: A deck of cards.

X be the number of aces obtained.


Hence, X can take value of 0, 1 or 2.


As we know, in a deck of 52 cards, 4 cards are aces. Therefore 48 cards are non- ace cards.


P(X = 0) = P(0 ace and 2 non ace cards)



P(X = 1) = P(1 ace and 1 non ace cards)



P(X = 2) = = P(2 ace and 0 non ace cards)



Hence, the required probability distribution is,


X



0



1



2



P(X)









Therefore Expectation of X E(X):






Hence, the correct answer is (D).

17

Chapter Exercises

More Exercise Questions