The probability of two students A and B coming to school on time are \frac{2}{7} and \frac{4}{7} ,  respectively. Assuming that the events ‘A coming on time’ and ‘B coming on time’ are independent, find the probability of only one of them coming to school on time.

 

 

 

 
 
 
 
 

Answers (1)

Let E1 : A comimg on time and 
      E2: B coming on time
Here p\left ( E_{1} \right )= \frac{2}{7},\; \; p\left ( \vec{E_{1}} \right )= \frac{5}{7}
        p\left ( E_{2} \right )= \frac{4}{7},\; \; p\left ( \vec{E_{2}} \right )= \frac{3}{7}
\therefore  p(only one on time) = p\left ( E_{1} \right )p\left ( \bar{E_{2}} \right )+p\left ( E_{2} \right )p\left ( \bar{E_{1}} \right )
                                     =\frac{2}{7}\times \frac{3}{7}+\frac{4}{7}\times \frac{5}{7}
                                     =\frac{26}{49}  
         

Preparation Products

Knockout JEE Main April 2021 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Mentorship from our Experts, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 14000/- ₹ 4999/-
Buy Now
Knockout NEET Aug 2021 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Mentorship from our Experts, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 14000/- ₹ 4999/-
Buy Now
Knockout JEE Main May 2021

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Mentorship from our Experts, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 22999/- ₹ 9999/-
Buy Now
Knockout NEET Aug 2021

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Mentorship from our Experts, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 22999/- ₹ 9999/-
Buy Now
Test Series JEE Main May 2021

Unlimited Chapter Wise Tests, Unlimited Subject Wise Tests, Unlimited Full Mock Tests, Get Personalized Performance Analysis Report,.

₹ 6999/- ₹ 2999/-
Buy Now
Boost your Preparation for JEE Main with our Foundation Course
 
Exams
Articles
Questions