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Chapter 13 Class 12 Probability
Example 6
Ex 13.1, 10 (a) Important
Ex 13.1, 12 Important
Example 11 Important
Ex 13.2, 7 Important
Ex 13.2, 11 (i)
Ex 13.2, 14 Important
Example 17 Important
Example 18 Important
Example 20 Important
Example 21 Important
Ex 13.3, 2 Important You are here
Ex 13.3, 4 Important
Ex 13.3, 8 Important
Ex 13.3, 10 Important
Ex 13.3, 12 Important
Ex 13.3, 13 (MCQ) Important
Question 4 Important Deleted for CBSE Board 2024 Exams
Question 5 Important Deleted for CBSE Board 2024 Exams
Question 6 Deleted for CBSE Board 2024 Exams
Question 7 Important Deleted for CBSE Board 2024 Exams
Question 8 Important Deleted for CBSE Board 2024 Exams
Question 3 Important Deleted for CBSE Board 2024 Exams
Question 6 Important Deleted for CBSE Board 2024 Exams
Question 11 Important Deleted for CBSE Board 2024 Exams
Question 15 Deleted for CBSE Board 2024 Exams
Question 10 Important Deleted for CBSE Board 2024 Exams
Question 11 Important Deleted for CBSE Board 2024 Exams
Question 4 Important Deleted for CBSE Board 2024 Exams
Question 6 Important Deleted for CBSE Board 2024 Exams
Question 10 Important Deleted for CBSE Board 2024 Exams
Question 13 Important Deleted for CBSE Board 2024 Exams
Question 13 Deleted for CBSE Board 2024 Exams
Example 23 Important
Question 2 Important Deleted for CBSE Board 2024 Exams
Question 4 Deleted for CBSE Board 2024 Exams
Question 6 Important Deleted for CBSE Board 2024 Exams
Misc 7 Important
Misc 10 Important
Chapter 13 Class 12 Probability
Last updated at Aug. 16, 2023 by Teachoo
Ex 13.3, 2 A bag contains 4 red and 4 black balls, another bag contains 2 red and 6 black balls. One of the two bags is selected at random and a ball is drawn from the bag which is found to be red. Find the probability that the ball is drawn from the first bag.4 Red (R) 4 Black (B) 2 Red (R) 6 Black (B) Let B1 : ball is drawn from Bag I B2 : ball is drawn from Bag II R : ball is drawn is red We need to find Probability that ball is drawn from Bag I, if ball is red = P(B1 |R) So, P(B1 |R) = (P(𝐵_1 ) . P(𝑅|𝐵_1))/(P(𝐵_1 ) . P(𝑅|𝐵_1)+P(𝐵_2 ) . P(𝑅|𝐵_2)) "P(B1 )" = Probability that ball is drawn from Bag I = 𝟏/𝟐 "P(R|B1)" = Probability that ball is red, if drawn from Bag I = 4/(4 + 4) = 4/8 = 𝟏/𝟐 "P(B1 )" = Probability that ball is drawn from Bag I = 𝟏/𝟐 "P(R|B1)" = Probability that ball is red, if drawn from Bag I = 4/(4 + 4) = 4/8 = 𝟏/𝟐 Putting values in formula, P(B1 |R) = (𝟏/𝟐 × 𝟏/𝟐)/(𝟏/𝟐 × 𝟏/𝟒 + 𝟏/𝟐 × 𝟏/𝟐) = (1/4 )/(1/8 + 1/4 ) = ( 2/8 )/( 3/8 ) = 2/3 Therefore, required probability is 𝟐/𝟑