Get Answers to all your Questions

header-bg qa

Explain Solution R.D. Sharma Class 12 Chapter 30 Probability  Exercise Multiple Choice Questions  Question 59 Maths Textbook Solution.

Answers (1)

Answer:\frac{3}{8}

Hint: You must know the rules of finding probability.

Given: P(A)=0.6, P(B)=0.2, P\left(\frac{A}{B}\right)=0.5

Solution:

As,

\begin{aligned} &P\left(\frac{A}{B}\right)=0.5 \\ &\frac{P(A \cap B)}{P(B)}=0.5 \\ &P(A \cap B)=0.5 P(B) \\ &P(A \cap B)=0.5 \times 0.2 \\ &P(A \cap B)=0.1 \end{aligned}

Also,

\begin{aligned} &P(\bar{B})=1-P(B)=1-0.2=0.8 \\ &P(A \cup B)=P(A) \times P(B)-P(A \cap B) \\ &=0.6+0.2-0.1=0.7 \end{aligned}

Now,

\begin{aligned} &P\left(\frac{\bar{A}}{\bar{B}}\right)=\frac{P(\bar{A} \cap \bar{B})}{P(\bar{B})} \\ &=\frac{P(\overrightarrow{A \cup B})}{0.8}=\frac{1-P(A \cup B)}{0.8} \\ &=\frac{1-0.7}{0.8}=\frac{0.3}{0.8}=\frac{3}{8} \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