Get Answers to all your Questions

header-bg qa

Need Solution for R.D.Sharma Maths Class 12 Chapter 30 Probability  Exercise 30.4 Question 15 Maths Textbook Solution.

Answers (1)

Answer: \frac{6}{2197}

Hint: Use permutations for finding  { }^{n} P_{r}=\frac{n !}{(n-r) !}

Given:

Three cards are drawn with replacement from a well shuffled pack of cards. Find the probability that the cards drawn are king, queen and jack.

Solution:

Let,

            A= Event of getting kings

             P\left ( A \right )=\frac{No.\: of\: cards\: of\: king}{Total\: no.of\: cards}=\frac{4}{52}

            Similarly, B= Event of getting queens

                           P\left ( B \right )=\frac{No.\: of\: cards\: of\: queens }{Total\: no.of\: cards}=\frac{4}{52}

                        C= Event of getting jacks

                        P\left ( C \right )=\frac{No.\: of\: jack\: cards\: }{Total\: no.of\: cards}=\frac{4}{52}

Probability that cards drawn are king, queen and jack  =\frac{4}{52}\times \frac{4}{52}\times \frac{4}{52}\times 3P_{2}

(Permutations has been used because the order of king,queen and jack can be changed) 

                                                                                   \begin{aligned} &=\frac{4 \times 4 \times 4 \times 6}{52 \times 52 \times 52} \\ &=\frac{6}{2197} \end{aligned}

Posted by

infoexpert21

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads