Since NCERT Books are changed, we are still changing the name of content in images and videos. It would take some time.

But, we assure you that the question is what you are searching for, and the content is the best -Teachoo Promise. If you have any feedback, please contact us.

Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class

Example 6 A die is thrown twice and the sum of the numbers appearing is observed to be 6. What is the conditional probability that the number 4 has appeared at least once? A dice is thrown twice
S =
We need to find the
Probability that 4 has appeared at least once,
given the sum of numbers is observed to be 6
Let F : Sum of numbers is 6
E : 4 Has appeared at least once
We need to find P(E|F)
Also,
E ∩ F = {(2, 4), (4, 2)}
P(E ∩ F) = 2/36
Let F : Sum of numbers is 6
E : 4 Has appeared at least once
We need to find P(E|F)
Also,
E ∩ F = {(2, 4), (4, 2)}
P(E ∩ F) = 2/36
E = {(1, 4), (2, 4), (3, 4), (4, 4),(5, 4),(6, 4),
(4, 1), (4, 2), (4, 3), (4, 5),(4, 6)}
P(E) = 11/36
F = {(1, 5), (5, 1), (2, 4), (4, 2), (3, 3)}
P(F) = 5/36
Now,
P(E|F) = (𝑃(𝐸 ∩ 𝐹))/(𝑃(𝐹))
= (2/36)/(5/36)
= 𝟐/𝟓
∴ Required probability is 2/5

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.

Hi, it looks like you're using AdBlock :(

Displaying ads are our only source of revenue. To help Teachoo create more content, and view the ad-free version of Teachooo... please purchase Teachoo Black subscription.

Please login to view more pages. It's free :)

Teachoo gives you a better experience when you're logged in. Please login :)

Solve all your doubts with Teachoo Black!

Teachoo answers all your questions if you are a Black user!