Get Answers to all your Questions

header-bg qa

Need solution for RD Sharma Maths Class 12 Chapter 30 Probability Exercise 30.3 question 18.

Answers (1)

Answer: \frac{3}{25}

Hint:   P(B \mid A)=\frac{P(A \cap B)}{P(A)}

Given,

            A=At least one die does not show 5

            B=The sum of the numbers on two dice is 8

Solution:

Clearly,
            

\begin{aligned} &A=\left\{\begin{array}{l} (1,1),(1,2),(1,3),(1,4),(1,6), \\ (2,1),(2,2),(2,3),(2,4),(2,6), \\ (3,1),(3,2),(3,3),(3,4),(3,6), \\ (4,1),(4,2),(4,3),(4,4),(4,6), \\ (6,1),(6,2),(6,3),(6,4),(6,6) \end{array}\right\} \\ &B=\{(2,6),(3,5),(4,4),(5,3),(6,2)\} \\ &A \cap B=\{(4,4),(6,2),(2,6)\} \end{aligned}

 Required Probability  =P(B \mid A)=\frac{P(A \cap B)}{P(A)}=\frac{3}{25}

Posted by

infoexpert24

View full answer

Crack CUET with india's "Best Teachers"

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