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Misc 8 - From employees of a company, 5 persons are selected

Misc 8 - Chapter 16 Class 11 Probability - Part 2
Misc 8 - Chapter 16 Class 11 Probability - Part 3
Misc 8 - Chapter 16 Class 11 Probability - Part 4
Misc 8 - Chapter 16 Class 11 Probability - Part 5

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Transcript

Misc 8 From the employees of a company, 5 persons are selected to represent them in the managing committee of the company. Particulars of five persons are as follows: A person is selected at random from this group to act as a spokesperson. What is the probability that the spokesperson will be either male or over 35 years? Total number of persons = 5 So, n(S) = 5 Probability spokesperson is male Let A be the event that person selected is male There are 3 males So, n(A) = 3 Probability spokesperson is male = P(A) = (𝑛(𝐴))/(𝑛(𝑆)) = 3/5 Probability spokesperson is over 35 years old Let B be the event that person selected is over 35 There are 2 person over 35 years old So, n(B) = 2 Probability spokesperson is over 35 years old = P(B) = (n(B))/(n(S)) = 2/5 We need to find probability that the spokesperson will be either male or over 35 year i.e. P(A ∪ B) We know that P(A ∪ B) = P(A) +P(B) – P(A ∩ B) To find P(A ∪ B), we must find P(A ∩ B) first P(A ∩ B) Probability that spokesperson is male & over 35 years old Here, 1 person is both male & over 35 years old So, n(A ∩ B) = 1 P(A ∩ B) = (𝑛(𝐴 ∩ 𝐵))/(𝑛(𝑆)) = 1/5 Now, P(A ∪ B) = P(A) +P(B) – P(A ∩ B) = 3/5 + 2/5 – 1/5 = (3 + 2 − 1)/5 = 4/5 Hence Probability that the spokesperson will be either male or over 35 year = P(A ∪ B) = 𝟒/𝟓

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.