

Get live Maths 1-on-1 Classs - Class 6 to 12
Examples
Example 2
Example 3
Example 4
Example 5 Important
Example 6
Example 7 Important
Example 8 You are here
Example 9 Important
Example 10
Example 11 Important
Example 12 Important
Example 13 Important
Example 14 Important
Example 15 Important
Example 16
Example 17 Important
Example 18 Important
Example 19 Important
Example 20 Important
Example 21 Important
Example 22
Example 23
Example 24 Important
Example 25 Important
Example 26 Important
Example 27
Example 28 Important Deleted for CBSE Board 2023 Exams
Example 29 Important
Example 30 Important Deleted for CBSE Board 2023 Exams
Example 31 Important Deleted for CBSE Board 2023 Exams
Example 32 Important Deleted for CBSE Board 2023 Exams
Example 33 Important
Example 34 Deleted for CBSE Board 2023 Exams
Example 35
Example 36 Important
Example 37 Important
Last updated at March 16, 2023 by Teachoo
Example 8 An urn contains 10 black and 5 white balls. Two balls are drawn from the urn one after the other without replacement. What is the probability that both drawn balls are black? We need to find probability that both balls drawn out are black Now, Probability both balls drawn are black = Probability first ball drawn is black × Probability second ball is black if first is black Finding both probabilities separately Probability first ball drawn is black There are 10 blacks balls out of 15 So, Probability = 10/15 = 2/3 Probability second ball drawn is black if first ball was black If first ball drawn was black, we are left with 9 black, 5 white balls So, Probability = (𝑅𝑒𝑚𝑎𝑖𝑛𝑖𝑛𝑔 𝐵𝑙𝑎𝑐𝑘 𝑏𝑎𝑙𝑙)/(𝑅𝑒𝑚𝑎𝑖𝑛𝑖𝑛𝑔 𝑏𝑎𝑙𝑙𝑠) = 9/14 Therefore, Probability both balls drawn are black = Probability first ball drawn is black × Probability second ball is black if first is black = 2/3 × 9/14 = 𝟑/𝟕